Include fontawesome icon in Markdown

I’m using PaperMod theme. It has few set of icons inbuilt. Idk how to use these icons in markdown. I like fontawsome icons to be in my markdown as well. What bothers me is, if i include fontawsome CDN, will it affect page load time? Also conflicts with themes?
Has someone tried this?

In the site I use, it’s added to the Hugo project using NPM/Node, the Fontawesome javascript file all.min.js is added to the site javascript using resources.Get. From there I can add icons using a fontawesome shortcode I wrote.

fontawesome.html looks like this:

<i class="{{ .Get "class" }}" style="
  font-size: {{ with .Get "font-size"}}{{.}}{{ else }}{{"2rem"}}{{ end }};
  border:{{ with .Get "border"}}{{.}}{{ else }}{{"2px solid"}}{{ end }}; 
  padding:{{ with .Get "padding"}}{{.}}{{ else }}{{"3px"}}{{ end }}; 
  border-radius:{{ with .Get "border-radius" }}{{.}}{{ else }}{{"3px"}}{{ end }};
  margin:{{ with .Get "margin" }}{{.}}{{ else }}{{"0 4px"}}{{ end }};
  {{ with .Get "color" }}color: {{ . | safeCSS }};{{end}}
  {{ with .Get "background-color" }}background-color: {{ . | safeCSS }};{{end}}"

I’d add an icon to page like this: {{< fontawesome class="fas fa-ellipsis-h" >}}

You have installed font with npm and you put all.min.js file inside /static folder. Then added shortcode ?

More or less. We don’t have the fonts installed, just the JS which adds the SVG. From there you can choose your method of adding the JS to your site and then the shortcode above should work.