It's not illegal to grow marijuana in my state, and while I know quite a few people that use marijuana recreationally or medically, I only know of a few that grow it themselves even though it's not particularly difficult.
It’s actually laughably easy. I did it once. I had zero gardening experience but did this indoors in a walk-in closet. It probably took a total of a regular work week of actual work and a few days of research beforehand, and I got over 1/4 lb. and was very high quality. But the main thing I got from it was a love of gardening haha.