Are you allowed to rename the AppComponent to something else?
From the default, AppComponent:
@Component({
    selector: 'app-root',
    templateUrl: './app.component.html',
    styleUrls: ['./app.component.css']
})
export class AppComponent {
    title = 'app';
}
To a new name, StockholmComponent:
@Component({
    selector: 'stockholm',
    templateUrl: './stockholm.component.html',
    styleUrls: ['./stockholm.component.css']
})
export class StockholmComponent {
    title = 'Stockholm';
}
 
    