Delete reference (Drawing workspace)
In the Delete dialog, you can delete objects in the Drawing workspace in Fusion.
Access the Delete dialog
On the toolbar, select Modify > Delete 
.
Selection
Click to select the object to delete.
Click multiple objects to select them individually, or click and drag to to select multiple objects at once.
To modify the selection set, click x Selected, then select additional objects.
To clear the selection set, next to x Selected, click the X.