Because of the Font Awesome license terms, Act2.1 has to use the Free version. If you have an active Font Awesome 5 Pro license and want to integrate it with Act2.1 please follow this guide.
To add an icon go to https://fontawesome.com/v5/search?m=free (or https://fontawesome.com/v5/search if you integrated Pro) and click the icon you need:
Then copy its code:
And paste it into your icon module in your template:
Or in your page:
Instead of a Font Awesome icon you can also add up to three characters, with a code like this:
<i>1</i>
Please see also the Icon component.