But here's my question, how hard or time consuming is it really, is it something anyone can pick up, or does it take a lot of dedication?
Hi, let me try to put the difficulty in perspective. My father was a photo hobbyist with a makeshift darkroom in the basement. When I was 5 years old it would have been probably beyond my capabilities to develop film (b&w only - color was wayyyy too difficult and expensive in those days). By the time I was 7 or 8 years old it would be no problem PROVIDED he was telling me what to do. Then, similar to Matt, I could do it all on my own by the time I was 10 or 11. But... I was using my father's equipment - darkroom, enlarger, etc.
And... I don't think I was disciplined enough to wait around and time things beyond the developer so I probably was fixing and washing the heck out of the film. After a few seconds in fixer I'd open the tank to see how the film looked, then leave it in there for a long while whilst I do more interesting things. Then similar thing with washing - fill and empty the tank a few times right away, let it sit for a while then come back for a few more fill and empty cycles, etc. (Fwiw back in those days we didn't have accurate digital timers and the like)
Today, I imagine I could probably teach an interested high school student the basics of film development in perhaps three 1-hour sessions on separate days. First day I might develop a roll while explaining what I'm doing. Second day have the student write down the steps in a notebook while discussing details. Third day, THEY do the mechanics, based on their notes. At this point I expect that they have a good enough start to rely on online instructions, etc. To be clear, I HAVE NOT ACTUALLY DONE THIS, just imagining how it might work.
Fwiw I've only talked about FILM developing. This leaves you with "NEGATIVES," where the tones are backwards. Wherever the original scene was light the film negative is dark. And vice versa. You likely would not even recognize one of your friends on a negative.
The conventional way to deal with this is to make a so-called print, perhaps a "contact print." For this all you need is a piece of glass and a light (with switch). (Plus the light-sensitive photo-paper and its developer and fixer. And a so-called safelight can be very helpful.) The photo-paper is much like film except that it is MUCH less sensitive to light and is on a white paper base.
So, to make a contact print you go into the dark and lay the negative on top of the photo-paper (emulsion towards emulsion so that signs/writing don't get reversed). Lay the glass on top to hold them tightly together (otherwise the print will be a bit blurry). Then turn on the light briefly; this will be determined by trial and error. But perhaps a second or less might be a good starting point.
A sort of strange thing happens. The photo paper reacts in a negative way (just like film); light makes the paper get dark (after being developed, of course). But... since the film is already negative, and it is used to expose a negative-reacting material (the photo paper) the final result is a normal appearing image - a "positive." Anyway, you develop (and fix, and wash, etc.) the photo paper. Now, it's almost certainly gonna be way too dark or too light, so you gotta change the exposure time. Then develop, etc. This is gonna be a tedious process of trial and error depending on how finicky you are. It would probably take another one or two 1-hour sessions to teach the minimum basics of this.
As a note the contact print is the same size as the negative, so you'll probably wanna use a "loupe," a strongish magnifier, to inspect the so-called "contact sheet." Just like the famous photojournalists or fashion photographers you've probably seen in older movies.
So, these are the basics. Which I think that most people with a sincere interest could learn, provided that they are at least 10 or 12 years old. After this you could carry on about as far as you want. I personally spent over 40 years working full-time in photography, most of it in lab or other technical work; always on a mission to learn more.