Plenty of people. If you have running water, some tape, and trashbags, you too could have a darkroom.
https://www.metmuseum.org/exhibitions/objects/objects@exhibi...
The roll itself can be manipulated too. Most of the techniques used in modern photoshop are basically 1:1 carry overs of darkroom processes. Layers, dodge and burn, masking, etc.
There was a time you could take this class in highschool.