Open Reference File - Xref

The best way to modify the reference file is open it
Select the reference file, then right-click > Open

 

A drawing reference will open in AutoCAD software
Image file will open according to the program in which file type of image associated
DWF underlay will open in Autodesk Design Review
DGN underlay cannot be open with AutoCAD software

Alternately, you can select the reference, right-click > Open Xref

 

When you close and save the open Xref

 

Alert balloon pop-up and prompt you to reload the reference file to show the changes