how to make this radius
as per the attachment, how this radius can be made. Can anyone help to make it possible?
I suppose you are interested in how to create the surface on which you measured a radius of 137.885 mm.
It is not a surface that would be created by using the Radius command. You need to use some other modeling technique. It's probably best to use surfaces and create that desired surface in parts. The trickiest part will be to create a transition of two surfaces with a radius of 137.885 mm.
I hastily created something similar, I created the surface in the corner as a Boundary surface. However, there are always lots of ways to do this ....