You can add content from ArcGIS Online and ArcGIS Enterprise portal to ArcGIS for AutoCAD using Add Data. Alternatively, you can add content by providing a URL to the ArcGIS Server Basicservice.
- On the main ribbon, click Add Data to expand the selection.
- Select Add Data by URL.
- Provide the URL of the service you want to add (a supported Enterprise service or portal item), and click Add.