Go, 124 bytes

Go Johnny, Go!

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import."strings"
func(s string)string{t,e:=Title(s),", "+s+"\n";m:=t+" Johnny "+s+e;return t+e+m+m+m+m+"Johnny B. "+t+"ode"}

Pure Bash, 69 76 bytes

M=aaaa;echo -e ${1^}, $1 ${M//a/\\n${1^} Johnny $1, $1}\\nJohnny B. ${1^}ode

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05AB1E, 37 bytes

™„, ¹J¹Ð™”ÿºÇ ÿ, ÿ”4.D¹™”ºÇ B. ÿode”»

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Explanation

™„, ¹J                                # concatenate title-cased input with ", " and input
     ¹Ð™                              # push input, input, title-cased input
        ”ÿºÇ ÿ, ÿ”                    # push the string "ÿ Johnny ÿ, ÿ" with "ÿ" replaced 
                                      # by title-cased input, input, input
                  4.D                 # push 3 copies of that string
                     ¹™               # push title-cased input
                       ”ºÇ B. ÿode”   # push the string "Johnny B. ÿode" with "ÿ" replaced 
                                      # by title-case input
                                   »  # join the strings by newlines

VIM, 54 49 Keystrokes (saved 1 keystroke from Kritixi Lithos)

yw~hC<Ctrl-R>", <Ctrl-R>0<Enter>Johnny B. <Ctrl-R>"ode<Esc}O<Ctrl-R>", Johnny <Ctrl-R>0, <Ctrl-R>0<Esc>3.         

Start with the word on a line on a file with the cursor at the first character, then this will replace it all with the text Explanation

1. Copy the word into a register, then change the first letter to be capitalized and save that to a register.
2. Write the first line using the registers to fill in the replacements and last lines
3. Write the second line using the registers to fill in the replacements
4. Repeat the middle line 3 times

Try it online! (Thanks DJMcMayhem!)

Batch, 207 bytes

@set s= %1
@for %%l in (A B C D E F G H I J K L M N O P Q R S T U V W X Y Z)do @call set s=%%s: %%l=%%l%%
@set j="%s% Johnny %1, %1"
@for %%l in ("%s%, %1" %j% %j% %j% %j% "Johnny B. %s%ode")do @echo %%~l

V, 41 bytes

ä$a, Ùäwa Johnny 5ÄGdwwcWB.W~Aode.ÎvU

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The perfect challenge for V!

Explanation:

ä$                              " Duplicate the input ('go' --> 'gogo', and cursor is on the first 'o')
  a, <esc>                      " Append ', '
                                " Now the buffer holds 'go, go'
          Ù                     " Duplicate this line
           äw                   " Duplicate this word (Buffer: 'gogo, go')
             a Johnny <esc>     " Append ' Johnny ' (Buffer: 'go Johnny go, go')
                           5Ä   " Make 5 copies of this line
G                               " Go to the very last line in the buffer
 dw                             " Delete a word
   w                            " Move forward one word (past 'Johnny')
    cW                          " Change this WORD (including the comma), to
      B.<esc>                   "   'B.'
             W                  " Move forward a WORD
              ~                 " Toggle the case of the character under the cursor
               Aode.<esc>       " Apppend 'ode.'
                         ÎvU    " Capitalize the first letter of each line

JavaScript (ES6), 104 101 99 bytes

(i,u=i[0].toUpperCase()+i.slice(1),x=`, ${i}
${u} Johnny `+i)=>u+x+x+x+x+`, ${i}
Johnny B. ${u}ode`

Previous version:

(i,u=i[0].toUpperCase()+i.slice(1))=>u+`, ${i}
${u} Johnny ${i}`.repeat(4)+`, ${i}
Johnny B. ${u}ode`

How it works:

• It's an anonymous function that takes the input as the parameter i

• Defines a variable u as the input i with the first letter capitalized (Note that this assumes input is nonempty, which is OK)

• Just directly construct the string to be returned from those two variables.

• Repeating the string "go, \nGo Johnny go" four times instead of repeating "Go Johnny go, go" saves one byte.

Edit 1: Forgot to golf out the semicolon, haha!! Also miscounted the bytes, it was originally 102, not 104. Thanks apsillers.

Edit 2: Instead of .repeat(4), by putting that string in a variable x and doing x+x+x+x allows saving two bytes.

Test snippet

let f = (i,u=i[0].toUpperCase()+i.slice(1),x=`, ${i}
${u} Johnny `+i)=>u+x+x+x+x+`, ${i}
Johnny B. ${u}ode`;

<input id=I type="text" size=70 value="code"><button onclick="console.log(f(I.value))">Run</button>

Pyth - 52 bytes

j", "_ArBQ3V4s[H" Johnny "G", "G;%"Johnny B. %sode"H

Test Suite.

Jelly, 41 bytes

5“ Johnny “, “¶”ẋj¹Ḋṙ7ỴŒu1¦€Y“B. ”⁸Œt“ode

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C, 156 151 bytes

i,a,b;B(char*s){a=*s++;printf("%c%s, %c%s\n",b=a-32,s,a,s);for(;++i%4;)printf("%c%s Johnny %c%s, %c%s\n",b,s,a,s,a,s);printf("Johnny B. %c%sode",b,s);}

Retina, 65 bytes

Byte count assumes ISO 8859-1 encoding.

^
$', 
:T01`l`L
:`,
 Johnny$',
:`$
¶$`
(\S+) (\S+ ).+$
$2B. $1ode

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Python, 94 bytes

lambda s:("|, #\n"+"| Johnny #, #\n"*4+"Johnny B. |ode").replace("|",s.title()).replace("#",s)

Python 3, 88 bytes

lambda x:("{0}, {1}\n"+4*"{0} Johnny {1}, {1}\n"+"Johnny B. {0}ode").format(x.title(),x)

A simple format string, with positional arguments.

C#, 219 211 212 146 Bytes

string x(string a){var b=(char)(a[0]^32)+a.Remove(0,1);var c="Johnny ";return$"{b}, {a}\n{"xxxx".Replace("x",$"{b} {c}{a}, {a}\n")}{c}B. {b}ode";}

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Explantation:

    string x(string a) {                            //Method that takes a string as Parameter
    var b = (char)(a[0] ^ 32)                       //Capitalize first letter of "a" 
        + a.Remove(0, 1);                           //append "a" with first letter removed
    var c = "Johnny ";                              //create variable that hold the string "Johnny " 
                                                    //In this example "go" was used as parameter
    return $"{b}, {a}\n                             //Go, go
    {"xxxx".Replace("x", $"{b} {c}{a}, {a}\n")}     //Create a Placeholder that holds "xxxx" 
                                                    //but Replace x with more placeholders and a newline
                                                    //Leading to the result of 4x Go Johnny go, go
    {c}B. {b}ode"; }                               //Johnny B. Goode

Output for testcases:

Go, go
Go Johnny go, go
Go Johnny go, go
Go Johnny go, go
Go Johnny go, go
Johnny B. Goode

Code, code
Code Johnny code, code
Code Johnny code, code
Code Johnny code, code
Code Johnny code, code
Johnny B. Codeode

A, a
A Johnny a, a
A Johnny a, a
A Johnny a, a
A Johnny a, a
Johnny B. Aode

Johnny, johnny
Johnny Johnny johnny, johnny
Johnny Johnny johnny, johnny
Johnny Johnny johnny, johnny
Johnny Johnny johnny, johnny
Johnny B. Johnnyode

Fantastic, fantastic
Fantastic Johnny fantastic, fantastic
Fantastic Johnny fantastic, fantastic
Fantastic Johnny fantastic, fantastic
Fantastic Johnny fantastic, fantastic
Johnny B. Fantasticode

Edit: Thanks to weston for suggesting using a function

MATLAB/Octave, 133 111 bytes

@(a)regexprep(['1, 2' 10 repmat(['1 32, 2' 10],1,4) '3B. 1ode'],{'1','2','3'},{[a(1)-32 a(2:end)],a,'Johnny '})

It's a start. Can hopefully be reduced further.

Basically it's an anonymous function which takes a string input and then uses regex to create the required output.

@(a)                                                    %Anonymous Function
    regexprep(                                          %Regex Replace
        ['1, 2' 10                                      %First line is: Code, code
            repmat(['1 32, 2' 10],1,4)                  %Then four lines of: Code Johnny code, code 
                               '3B. 1ode'],             %Final line: Johnny B. Codeode
         {'1','2','3'},                                 %1,2,3 are our replace strings in the lines above
         {[a(1)-32 a(2:end)],a,'Johnny '}               %We replace with '(I)nput', 'input' and 'Johnny ' respectively.
    )

An example:

@(a)regexprep(['1, 2' 10 repmat(['1 32, 2' 10],1,4) '3B. 1ode'],{'1','2','3'},{[a(1)-32 a(2:end)],a,'Johnny '});
ans('hi')
ans =

Hi, hi
Hi Johnny hi, hi
Hi Johnny hi, hi
Hi Johnny hi, hi
Hi Johnny hi, hi
Johnny B. Hiode

You can sort of Try it online!. The code doesn't quite work with Octave as all the upper case letters become ${upper($0)}, whereas in MATLAB this is converted to the actual upper case letter.

Given the input is guaranteed to only be a-z (lowercase alphabet), I can save 22 bytes by using a simple subtraction of 32 to convert the first letter in the string to capital, rather than using regex with the upper() function.

As a result, the code now works with Octave as well, so you can now Try it online!

Ruby, 89 88 86 79 bytes

My first golf submission :

->x{"^, *
#{"^ Johnny *, *
"*4}Johnny B. ^ode".gsub(?^,x.capitalize).gsub ?*,x}

Thanks a lot to @manatwork for his awesome comment : 7 bytes less!

PHP, 88 Bytes

<?=$u=ucfirst($l=$argv[1]),", $l\n",$r="$u Johnny $l, $l\n","$r$r{$r}Johnny B. {$u}ode";

Stacked, 64 bytes

:@n tc@N('%N, %n
'!'%N Johnny %n, %n
'!4*'Johnny B. 'N'ode'!)sum

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JavaScript, 98

s=>[S=s[0].toUpperCase()+s.slice(1),[,,,].fill(` ${s}
${S} Johnny `+s)]+`, ${s}
Johnny B. ${S}ode`

Abuses array-to-string serialization to create commas. Builds an array of the form:

["Go",
 " go\nGo Johnny go", (repeated...)]

And concatenates it to the string of the form ", go\nJohnny B. Goode":

["Go",
 " go\nGo Johnny go",
 " go\nGo Johnny go",
 " go\nGo Johnny go",
 " go\nGo Johnny go"] + ", go\nJohnny B. Goode"

Nova, 105 bytes

a(String s)=>"#{s.capitalize()+", #s\n"+"#s.capitalize() Johnny #s, #s\n"*4}Johnny B. #s.capitalize()ode"

Because Nova (http://nova-lang.org) is extremely early beta (and buggy), there are some obvious handicaps that are in place here keeping it from using even less bytes.

For example, could have saved capitalized function call (which is called 3 times) in a local variable like this:

a(String s)=>"#{(let c=s.capitalize())+", #s\n"+"#c Johnny #s, #s\n"*4}Johnny B. #{c}ode"

which would have taken the byte count down to 89 bytes. The reason this doesn't work now can be blamed on the argument evaluation order in the C language, because Nova is compiled to C. (The argument evaluation order will be fixed in a future update)

Even more, I could have introduced a "title" property in the String class (and I will after doing this lol) to reduce the count from the capitalization function call:

a(String s)=>"#{(let c=s.title)+", #s\n"+"#c Johnny #s, #s\n"*4}Johnny B. #{c}ode"

and that would free up 7 bytes to a new total of 82 bytes.

Furthermore (and further off), once lambda variable type inference is added, this would be valid:

s=>"#{(let c=s.title)+", #s\n"+"#c Johnny #s, #s\n"*4}Johnny B. #{c}ode"

The count could be brought down to 72 bytes.

By the way, this is my first code golf, so I probably have missed even more optimizations that could have been made. And this being a non-golf centric, general purpose language, I think it's pretty impressive.

The first 105 byte code works in the current Nova Beta v0.3.8 build available on http://nova-lang.org

class Test {
    static a(String s)=>"#{s.capitalize()+", #s\n"+"#s.capitalize() Johnny #s, #s\n"*4}Johnny B. #s.capitalize()ode"

    public static main(String[] args) {
        Console.log(a("expl"))
    }
}

outputs:

Expl, expl
Expl Johnny expl, expl
Expl Johnny expl, expl
Expl Johnny expl, expl
Expl Johnny expl, expl
Johnny B. Explode

Thank you for listening to my shameless advertisement for the general purpose language Nova (found at http://nova-lang.org ...get it now!!)

Java 7, 151 147 146 bytes

String c(String s){String x=(char)(s.charAt(0)^32)+s.substring(1),n=s+"\n",c=", ",r=n+x+" Johnny "+s+c;return x+c+r+r+r+r+n+"Johnny B. "+x+"ode";}

Explanation:

String c(String s){                           // Method with String parameter and String return-type
  String x=                                   //  Temp String with: 
           (char)(s.charAt(0)^32)             //   The first letter capitalized
    + s.substring(1),                         //   + the rest of the String
         n=s+"\n",                            //  Temp String with input + new-line
         c=", ",                              //  Temp String with ", "
         r=n+x+" Johnny "+s+c;                //  Temp String with "input\nInput Johnny input, "
  return x+c+r+r+r+r+n+"Johnny B. "+x+"ode";  //  Return output by putting together the temp Strings
}                                             // End of method

Test code:

Try it here.

class M{
  static String c(String s){String x=(char)(s.charAt(0)^32)+s.substring(1),n=s+"\n",j=" Johnny ",c=", ",r=n+x+j+s+c;return x+c+r+r+r+r+n+"Johnny B. "+x+"ode";}

  public static void main(String[] a){
    System.out.println(c("go"));
    System.out.println();
    System.out.println(c("code"));
    System.out.println();
    System.out.println(c("a"));
    System.out.println();
    System.out.println(c("johnny"));
    System.out.println();
    System.out.println(c("fantastic"));
  }
}

Output:

Go, go
Go Johnny go, go
Go Johnny go, go
Go Johnny go, go
Go Johnny go, go
Johnny B. Goode

Code, code
Code Johnny code, code
Code Johnny code, code
Code Johnny code, code
Code Johnny code, code
Johnny B. Codeode

A, a
A Johnny a, a
A Johnny a, a
A Johnny a, a
A Johnny a, a
Johnny B. Aode

Johnny, johnny
Johnny Johnny johnny, johnny
Johnny Johnny johnny, johnny
Johnny Johnny johnny, johnny
Johnny Johnny johnny, johnny
Johnny B. Johnnyode

Fantastic, fantastic
Fantastic Johnny fantastic, fantastic
Fantastic Johnny fantastic, fantastic
Fantastic Johnny fantastic, fantastic
Fantastic Johnny fantastic, fantastic
Johnny B. Fantasticode

CJam, 50 bytes

r:L(eu\+:M',SLN[MS"Johnny ":OL',SLN]4*O"B. "M"ode"

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Explanation:

r:L(eu\+:M',SLN[MS"Johnny ":OL',SLN]4*O"B. "M"ode" e# Accepts an input token.
r:L                                                e# Gets input token and stores it in L.
   (eu\+:M                                         e# Converts token to uppercase-first and stores it in M.
          ',S                                      e# Appears as ", ".
             L                                     e# Input token.
              N                                    e# Newline.
               [                                   e# Opens array.
                M                                  e# Modified token.
                 S                                 e# Space.
                  "Johnny ":O                      e# Pushes "Johnny " and stores it in O.
                             L                     e# Input token.
                              ',SLN                e# The same {',SLN} as before.
                                   ]4*             e# Closes array and repeats it 4 times.
                                      O            e# "Johnny ".
                                       "B. "       e# "B. ".
                                            M      e# Modified token.
                                             "ode" e# "ode".

Pyke, 43 bytes

l5j", "Qs3
Qld"Johnny "iQs3:D4i"B. ode"+Tj:

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Constructs and prints the first line then inserts Johnny go before the comma and duplicates that 4 times. Finally constructs the last part.

VBA, 138 Bytes

Subroutine that takes variant input b of assumed type string, and outputs by printing the the VBE immediates window

Sub a(b)
n=vbCr
c=b
Mid(c,1,1)=UCase(b)
s=c &", " &b
For i=1To 4
s=s &n &c &" Johnny " &b &", " &b
Next
Debug.?s &n &"Johnny B. " &c &"ode"
End Sub

Example Case

a "an"          ''  <- subroutine call
An, an          ''  <- output
An Johnny an, an
An Johnny an, an
An Johnny an, an
An Johnny an, an
Johnny B. Anode

Kotlin, 112 Bytes

fun g(s:String):String{val u=s.capitalize();return "$u, $s\n${"$u Johnny $s, $s\n".repeat(4)}Johnny B. ${u}ode"}

Ungolfed:

fun g(s: String): String {
    val u = s.capitalize()
    return "$u, $s\n${"$u Johnny $s, $s\n".repeat(4)}Johnny B. ${u}ode"
}

Python, 258 bytes

from jinja2 import Template
def f(go):
    t = Template("""{{ Go }}, {{ go }}
{{ Go }} Johnny {{ go }}, {{ go }}
{{ Go }} Johnny {{ go }}, {{ go }}
{{ Go }} Johnny {{ go }}, {{ go }}
{{ Go }} Johnny {{ go }}, {{ go }}
Johnny B. {{ Go }}ode""")
    return t.render(Go=go.title(), go=go)

Java 6, 258 242 bytes

enum j{;public static void main(String[]a){char[]b=a[0].toCharArray();b[0]^=32;System.out.printf("%1$s, %2$s\n%1$s %3$s%2$s, %2$s\n%1$s %3$s%2$s, %2$s\n%1$s %3$s%2$s, %2$s\n%1$s %3$s%2$s, %2$s\n%3$sB. %1$sode",new String(b),a[0],"Johnny ");}}

Longest part of it is the format for printf. There are problems with input different than string from a to z(yes I know I don't need to support anything else).

Ungolfed with comments:

enum j {
    ;

    public static void main(String[] a) {
        char[] b = a[0].toCharArray();              // Copy of the input string
        b[0]^=32;                                   // First character of copy to uppercase
        System.out.printf(
                "%1$s, %2$s\n%1$s %3$s%2$s, %2$s\n%1$s %3$s%2$s, %2$s\n%1$s %3$s%2$s, %2$s\n%1$s %3$s%2$s, %2$s\n%3$sB. %1$sode", // Format string
                new String(b),  // Capitalized string
                a[0],           // Original input string
                "Johnny ");     // "Johnny "
    }
}

EDIT: Golfed 16 bytes thanks to weston

Pure Bash, 72 bytes (modified version of R. Kapp's answer):

M=hnny;echo -e ${1^}, $1 ${M//?/\\n${1^} Jo$M $1, $1}\\nJo$M B. ${1^}ode

Japt, 62 56 bytes

[1S]+U+R+`1 Johnny 0, 0
`²²+`Johnny B. 1o¸` d0U1Ug u +UÅ

Try it online!

62-byte solution using a substantially different technique:

Saved 3 bytes thanks to ETHproductions

W=Ug u +UÅ)+", {U}
"+`{W} Johnny {U}, {U}
`²²+`Johnny B. {W}o¸

Try it online!

C#, 159 130 bytes

Golfed

(i)=>string.Format("{0},{1}????\n{2} B. {0}ode".Replace("?","\n{0} {2}{1},{1}"),(i[0]+"").ToUpper()+i.Substring(1)," "+i,"Johnny");

Ungolfed

( i ) => string.Format( "{0},{1}????\n{2} B. {0}ode"
    .Replace( "?", "\n{0} {2}{1},{1}" ),

    ( i[ 0 ] + "" ).ToUpper() + i.Substring( 1 ), // {0}
    " " + i,                                      // {1}
    "Johnny" );                                   // {2}

Ungolfed readable

( i ) => string.Format( @"{0},{1}
    ????
    {2} B. {0}ode"

    // Replaces the '?' for the string format that contains the 
    // repetition of "___ Johnny ___, ___".
    .Replace( "?", "\n{0} {2}{1},{1}" ),

    // {0} - Converts the first letter to upper,
    //       then joins to the rest of the string minus the first letter
    ( i[ 0 ] + "" ).ToUpper() + i.Substring( 1 ),
    // {1} - The input padded with a space, to save some bytes
    " " + i,
    // {2} - The name used as parameter, to save some bytes
    "Johnny" );

Full code

using System;

namespace Namespace {
    class Program {
        static void Main( string[] args ) {
            Func<string, string> func = ( i ) =>
                string.Format( "{0},{1}????\n{2} B. {0}ode"
                    .Replace( "?", "\n{0} {2}{1},{1}" ),

                    ( i[ 0 ] + "" ).ToUpper() + i.Substring( 1 ),
                    " " + i,
                    "Johnny" );

            int index = 1;

            // Cycle through the args, skipping the first ( it's the path to the .exe )

            while( index < args.Length ) {
                Console.WriteLine( func( args[index++] ) );
            }

            Console.ReadLine();
        }
    }
}

Releases

• v1.1 - -29 bytes - Thanks to Sir Bitesalot last update, who remembered me I could edit the string before format.
• v1.0 - 159 bytes - Initial solution.

Notes

The title has a link to a page with the code and the test cases. Just hit Go and the result will be printed below the code.