Available with Business Analyst license.
The image below shows how to access Add Online Maps and Layers in Business Analyst. A similar way to add online services is through File > Add Data > Add Data from ArcGIS Online. You can add basemaps or data from the ArcGIS Online community or your organization account.
The default map layers are installed to C:\ArcGIS\Business Analyst\US_2022\Datasets\ArcGIS Online Maps.
Newly saved map services or layers must be saved to C:\My Output Data\ArcGIS Online Maps.