How do you hide and unhide a certain group in a model using procedures

Hello, I have been making a shelf in Minecraft, and I am making it so that when you put an item into one of the slots, it appears on the block model itself. (almost like a chiseled bookshelf + chest)
I was going to do this, but i actually dont know any way you could hide or unhide certain groups or parts of a model. Does anyone know how to do this? TY