Interactive menu system in Bash [closed]

This is a simple loop menu script that I have for class. The goal was to make a menu with applicable commands.

Menu:

• A. Greet me. (Greet the user by their username (using the whoami command with back ticks))
• B. Create a file in my home directory. (Ask the user what they want to name the file. Make sure the file does not already exist, using an if statement)
• C. Search for a file. (Ask the user for the starting location of the file and the name. Use the find command)
• D. Exit

I have 0 confidence in my scripting skills as I'm learning, so could you help me out? I don't know if put ;; at the end of choices like touch filescript;; read filescript;;, so on. Also, I'm not very sure of my choice C, creating in home directory.

#!/bin/bash
#
# This is Script 2 written by Jake Smoak
#
#
CHOICE=7
until [ $CHOICE -eq 4 ]
do
clear
echo Please select a menu item
echo
echo "A.) "Greet Me"
echo "B.) "Create a file in my home directory"
echo "C.) "Search for a file"
echo "D.) "Exit"
echo
read CHOICE
case $CHOICE in
A) echo "Hello $(whoami)."
B) echo "What would like to name the file?"
touch FILENAME;;
if [ -a $FILENAME ]
then 
echo "Sorry, this file is already made"
C) echo -n "Enter the location where the search should start. "
read STARTLOCATION
echo -n "What is the name of the file to search for? "
read FILENAME
echo "Search starting for the $FILENAME file in the $STARTLOCATION directory"
find $STARTLOCATION -name $FILENAME 2> /dev/null
D) echo "Sorry to see you go :("
*) echo You have made a mistake, Please try again"
esac
echo "Press Enter to continue"
read Enter
done