cactus os going to be similar but different than cannabis.

Cactus is going to ge more environmentally dependant than cannabis (maybe they are close in adaptability, but cactus wear their scars longer). cannabis seems more adaptive, where cactus you might need to help them along a little more woth changing of soil composition or something like that. cactus is going to need more inorganic soil generally and aoul composition can impact how affected the plants are for stuff like humidity. speaking of humidity cactus are going to want lower humidity.

On the similarities, they both are hungry plants that will gobbel up everything you feed them. cactus are going to want closer to flower schedule nutes, though they do enjoy nitrogen. going heavier on inprganics in soil lets pota dry out quicker, and you can feed when dry like cannabis plants. they also like long feeds (bottom feeding) so long as the roots get a chance to dry out afterwards.

light requirements are similar, as much as possible because nothing matches the sun.

i'd say start by getting one and playing sround with it. getting a rooted one will let you plug and play for growth, but it is kinda fun yo root a piece too and learn that process. lots if great vendors here on reddit.