Step 1:
Please get Foxit Reader button from https://www.foxitsoftware.com/img/icon_getreader.gif and upload it to your website server.

Step 2:
Add the below code to your website's homepage:
<a href="http://cdn01.foxitsoftware.com/pub/foxit/reader/desktop/win/3.x/3.3/enu/FoxitReader331_enu_Setup.exe">
<img border="0" src="icon_getreader.gif" width="88" height="31"></a>

Note: The src above is the path where you input to save the icon_getreader.gif picture.