I am using Font Awesome and do not wish to add CSS with HTTP. I downloaded Font Awesome and included it in my code, yet Font Awesome is showing a bordered square box instead
Check that the path to your CSS file is correct. Rather prefer absolute links, they are easier to understand since we know where we start from and search engines will also prefer them over relative links. And to reduce bandwidth rather use the link from font-awesome servers:
Moreover if you use it, there will be no need of uploading extra fonts to your server and you will be sure that you point to the right CSS file, and you will also benefit from the latest updates instantly.