fontawesome icons cdnjs code example
Example 1: fontawesome cdn
<link href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.13.0/css/all.min.css" rel="stylesheet">
Example 2: font awesome cdn
<link rel="stylesheet" href="https://pro.fontawesome.com/releases/v5.10.0/css/all.css" integrity="sha384-AYmEC3Yw5cVb3ZcuHtOA93w35dYTsvhLPVnYs9eStHfGJvOvKxVfELGroGkvsg+p" crossorigin="anonymous"/>