Check out the How to get help on the Dynamo forums post
What have you tried so far?
I would suggest this is not as easy as it sounds
Firstly I would review what Revit can already do - curtain walls can be cut by windows with openings when you join an external wall to an internal wall even with a gap. Then all you would have to do is copy the wall, change the type and join
Synthesize have some nodes which can join geometry