How to angle/lean part of a wall

Hello again,

How do I lean the top part of my wall towards inside (top part of it is sloped)? I have this part in a separate group and I believe I need to use the rotate tool on the red axis at the bottom left corner but the red axis won’t appear: I only see green, blue and black.

Thank you!

Tap the right arrow to lock the red axis of the rotate tool.

Thank you! I was able to find the red red axis for that, but was unsuccessful in placing the top part of the wall at angle. I think it’s difficult to do once all the walls of the apartment are erected. I will try to rebuild the kitchen with those funky walls separately and start my drawing in 2D.