Angular 10 – can’t bind to ‘formGroup’ since it isn’t a known property of ‘form’

In your login.component.ts there is no selector for component, It should be like this:

@Component({
  selector: 'app-login',
  templateUrl: './login.component.html',
  styleUrls: ['./login.component.css']
 })

In addition in app.module.ts, put LoginComponent in the declarations. You put it in imports which is incorrect.