I want to put some fontawesome icons in my readme to explain what they mean in my website but markdown doesnt allow css so is there a way I can overcome this?
This is where I got the icon
This would be the html <i class="fas fa-crown"></i>
This is the stylesheet link
<link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.14.0/css/all.css" integrity="sha384-HzLeBuhoNPvSl5KYnjx0BT+WB0QEEqLprO+NBkkk5gbc67FTaL7XIGa2w1L0Xbgc" crossorigin="anonymous">
Simple, you can't!
What you can do is download the image you want and include it, for example:
![fa-crown](fa-crown.svg)
or
<img src="fa-crown.svg" width="50" height="50">
If you want to learn more: GitHub Flavored Markdown Spec
Update
You can also use the FontAwesome images hosted on the FontAwesome GitHub repo. Therefore you can use it like this:
<img src="https://raw.githubusercontent.com/FortAwesome/Font-Awesome/6.x/svgs/solid/crown.svg" width="50" height="50">
You will see this: