I have a question in photoshop, can someone help?

I have this picture I wish to use as a template for cassette stickers. I would like to paste images on this picture, but the black rectangle in the middle is always covered, it's not wanted... The goal is to have the black part always remain black, even if I paste images or texts on the white parts... Should I use Layers? Or is it possible to define a zone of "disabled modifications"?

(The black part will be cut by hand with cissors)

Just put the black rectangle as one layer on top of all the other layers and it should be fine. I can think of a few other ways to do it.