declare var require: any;

@Component({...})
export class MapComponent implements OnInit, OnDestroy {

  private chart;
  isBrowser: boolean

  constructor(
    @Inject(PLATFORM_ID) private platformId: Object
  ) {
    this.isBrowser = isPlatformBrowser(platformId)
  }

  ngOnInit(): void {
    if (this.isBrowser) {
      this.setUpChart();
    }
  }


  setUpChart() {
    if (this.isBrowser) {

      const am4core = require("@amcharts/amcharts4/core");
      const am4maps = require("@amcharts/amcharts4/maps");

      let chart = am4core.create("world-map", am4maps.MapChart);
      // ...
    }
  }