Surface hierarchy

Brep accepts to extract trim curves? Or I need a brepface? I want untrim a suface and keep trim curves.
What is the surface hierarchy?

A surface is a single-face Brep. You can convert a surface to a brep using surface.ToBrep(). You might be able to get what you want directly from the Brep with Brep.DuplicateNakedEdgeCurves(). Otherwise, you will need to get the Brep’s single face and work with that.

Resulted in Array[Curve] (())
How do I draw back in Rhino?

I was able to draw the curves … perfect