To add an icon or image simple locate a website which generates favicon.ico images. Once you have the .ico file which is the small version of your image that will placed in the browser before your url, download the file to your root web file on your selected server.
Add this code to you index.html or main file:
<link rel=”shortcut icon” type=”image/x-icon” href=”/favicon.ico”>
This code should be placed in the <head> tag of your file.