best layout fo a fixed part (on the left) and a dynamic part (on the right)

[mcanonic]

Ok, thank you.
If I'm not wrong, I need a parent layout that in my case could be a QHBoxLayout, which will contain a QVBoxLayout (the lest panel) and a QStackWIdget (on the right panel). Maybe I'm wrong since the QStackWidget is not a layout.
Two more questions.
Any time a button is click on the left panel, I have to remove all widgets in the right panel. Should I looking for any widget in the right panel and delete it one-by-one?
May I add a vertical line between the left panel and the right one?
Thanks for your support and patience.
M