Check out example codes for "how to use icon in html". It will help you in understanding the concepts better.

Code Example 1

<i class="fas fa-band-aid"></i>
<i class="fas fa-cat"></i>
<i class="fas fa-dragon"></i>
<i class="far fa-clock"></i>
<i class="fas fa-clock"></i>

Code Example 2

<!DOCTYPE html>
<html>
<head>

     <script src="https://kit.fontawesome.com/yourcode.js"></script>

   <!--Get your code at fontawesome.com-->
</head>
<body>

<i class="fas fa-band-aid"></i>
<i 
   class="fas fa-cat"></i>
<i class="fas fa-dragon"></i>
<i class="far fa-clock"></i>

   <i class="fas fa-clock"></i>


  </body>
</html>

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