app.component.ts

import { Component } from '@angular/core';

@Component({
  selector: 'my-app',
  template: '<h1>Hello World</h1>'
})
export class AppComponent {
  
}

app.module.ts

import { NgModule }      from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';


import { AppComponent }  from './app.component';
import { FormsModule }   from '@angular/forms';


@NgModule({
  imports:      [ BrowserModule, FormsModule ],
  declarations: [ AppComponent ],
  bootstrap:    [ AppComponent ]
})
export class AppModule { }

main.ts

import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { AppModule } from './app.module';
platformBrowserDynamic().bootstrapModule(AppModule);