How to use the angular-cesium.AngularCesiumModule.forRoot function in angular-cesium

import { EllipsesEditorExampleComponent } from './components/editor-layer/ellipses-editor-layer/ellipses-editor-example.component';
import { AppMaterialModule } from './app.material.module';
import { SingleEntityOnMapExampleComponent } from './components/single-entity-on-map-example/single-entity-on-map-example.component';
import { MyCustomContextMenuComponent } from './components/context-menu-layer/context-menu/my-custom-context-menu.component';
import { BillboardLayerExampleComponent } from './components/billboard-layer-example/billboard-layer-example.component';
import { CylinderLayerExampleComponent } from './components/cylinder-layer-example/cylinder-layer-example.component';
import { EllipsoidLayerExampleComponent } from './components/ellipsoid-layer-example/ellipsoid-layer-example.component';
import { VolumeLayerExampleComponent } from './components/volume-layer-example/volume-layer-example.component';
import { WallLayerExampleComponent } from './components/wall-layer-example/wall-layer-example.component';


@NgModule({
  imports: [
    BrowserModule,
    FormsModule,
    AngularCesiumModule.forRoot(),
    AngularCesiumWidgetsModule,
    BrowserAnimationsModule,
    AppMaterialModule,
  ],
  declarations: [
    AppComponent,
    BillboardLayerExampleComponent,
    WallLayerExampleComponent,
    CylinderLayerExampleComponent,
    EllipsoidLayerExampleComponent,
    VolumeLayerExampleComponent,
    LabelLayerExampleComponent,
    EllipseLayerExampleComponent,
    CircleLayerExampleComponent,
    EllipseLayerComponent,
    PolylineLayerExampleComponent,

@NgModule({
  declarations: [
    AppComponent,
    MainMapComponent,
    ToolbarExampleComponent,
    MyCustomContextMenuComponent,
    ContextMenuLayerComponent,
    KeyboardControlLayerComponent,
    UFOsLayerComponent,
    NavBarComponent,
    AboutComponent
  ],
  imports: [
    BrowserModule,
    AngularCesiumModule.forRoot(),
    AngularCesiumWidgetsModule,
    FontAwesomeModule
  ],
  entryComponents: [MyCustomContextMenuComponent],
  providers: [MockDataProviderService],
  bootstrap: [AppComponent]
})
export class AppModule {
}