How to: Http, rest, authentication, angular, stencil, pwa, v4?

I’m trying to wrap my head around how to do http rest calls with ionic v4/stencil/angular, etc. for a progressive web app. Should I directly be using angular components, viz.

import { HttpClientModule } from ‘@angular/common/http’;

Any tips on how to get started would be appreciated. Thanks.

I went with Javascript native fetch() for simple REST (that sends the request not as JSON body but like a regular form).