how to link a font awesome icon code example
Example 1: font awesome icons link
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
Example 2: link to font awesome
<link rel="stylesheet" href="path/to/font-awesome/css/font-awesome.min.css">