Font Awesome 5 font-family issue

Question

I integrated Font Awesome 5 in a project with bootstrap 4. When I recall a font via CSS it does not work. with Font Awesome 4 the code was as follows:

#mainN         


        

Answer 1

that's probably about pricing model... ;)

https://fontawesome.com/how-to-use/on-the-web/referencing-icons/basic-use

Solid    Free           fas    
Regular  Pro Required   far    
Light    Pro Required   fal    
Brands   Free           fab