How many different way to insert image in magento cms page?

Using the "Insert Image" button will add the images which are relative to the media wysiwyg directory

img src="{{media url="wysiwyg/filename.jpg"}}" alt="" />

You could also have images stored as the content of a static block and then call them into the cms page contact using either using

{{block type="cms/block" block_id="staticblock_identifier"}}

Or use the widget interface and select Widget Type "CMS Static Block" which will add blocks by id like

{{widget type="cms/widget_block" template="cms/widget/static_block/default.phtml" block_id="10"}}

If you'd like the image to appear just above or below the main content look at adding it through layout XML and adding a static block either for that page using the CMS page design tab or for every CMS page using the "cms_page" layout handle.

If your image is stored as a static block and you'd like it before the main content add the following XML to your page or cms handle.

<reference name="content">
    <block type="cms/block" before="-">
        <action method="setBlockId"><block_id>staticblock_identifier</block_id></action>
    </block> 
</reference>

If you'd like the block to come after the content enter

after="-"