The browser won't make a request for every webfont although they're all in the CSS

I clicked this link: https://5e9c012d3f93e40006beb655--hello-64bit.netlify.app/

Your HTML (line 71) reads:

<i class="fa fa-twitter"></i>

And your hello.css (parsed, line 4512) reads:

.fab {
  font-family:'Font Awesome 5 Brands';
  font-weight:400
} 

Obviously you need to change line 71 to:

<i class="fab fa-twitter"></i>

Happy coding!