Ah sorry didnt see this. Thank you so much for the help though. I followed the instructions you gave above but changed just the icon name to the one i liked on font awesome and it is not showing anything.
Website is jackclub.shop and the password is "password" if you would like to look at the site
<link href="https://stackpath.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet" integrity="sha384-wvfXpqpZZVQGK6TAh5PVlGOfQNHSoD2xbE+QkPxCAFlNEevoEH3Sl0sibVcOQVnN" crossorigin="anonymous">
<script
src="https://code.jquery.com/jquery-1.12.4.min.js"
integrity="sha256-ZosEbRLbNQzLpnKIkEdrPv7lOy9C27hHQ+Xp8a4MxAQ="
crossorigin="anonymous"></script>
<script>
$(".Cart-inner").append("<i class='fas fa-cash-register' aria-hidden='true'></i>");
</script>