Combine two shapes and hollow inside

Hello,

I’m just learning Sketchup and I’m trying to combine two shapes and hollowing the part inside.
I made a schema to describe my problem.
I don’t have any idea how to do that…

How would you do or which plugin may I use?

Thanks for your help

Select both objects, right-click, Intersect/With Selection, and afterwards you should be able to delete the faces that shouldn’t be there.

Thank you! That is great.