the steps you are describing are related to including font-awesome 4.7, by doing npm install font-awesome you are installing I guess font-awesome >= 5 (which I think should not be imported the same way)
I would strongly recommend using v5 instead. It is so much easier to integrate. You don’t have to fool with any SCSS, font paths, custom build script modifications, or anything. All you have to do is add something along the lines of these three lines anywhere in your app TS:
import fontawesome from "@fortawesome/fontawesome";
import solid from '@fortawesome/fontawesome-free-solid';
fontawesome.library.add(solid as any);
The situation involving tree-shaking and including only the icons you want to use in your app bundle are in flux at the moment, so check back once 5.1 is released, but what you see above should get you the entire free solid pack in the current version as of now (5.0.8).