The only SW canon are the 6 movies. Everything else that's considered canon is part of the expanded universe.
Jedi is a title, so even if you managed to train yourself in the force (which is impossible as far as I know), you still can't become one. As for Sith, I think anyone can become one. You don't even need to be proficient with the force, you just need to be force sensitive.
I meant within the expanded universe. Sorry for not clarifying. But that's why I added the "force adept". So not necessarily a Jedi or Sith, but they know how to utilize the force.
A game without the galaxy about to be destroyed. More of a personal journey. Hence the character who kinda trains himself for his own reasons, and uses his power for his own agendas.
There are some whose history is unknown, but there is nobody known who trained himself.
He is the player character of Jedi Outcast, correct?
Yes. He's the player character in the Dark Forces/Jedi Knight games, but not Jedi Academy.
I never had the pleasure of playing any of them, just read random things about them (maybe a review once). Any copies available for any consoles, or were they all PC titles?
Either way, I'm sure they aren't very demanding, hardware wise, so even my laptop should run them if I decide try and pick them up.
Dark Forces is on PS1 (available on PSN) and Jedi Knight II: Jedi Outcast was released on the Game Cube and Xbox. Jedi Knight: Dark Forces II was not released on any console. I'm having a hard time remembering exactly what happened in the games. Part of me thinks he was trained by a ghost, and the other part of me thinks that he was only told about his father (or something like that) by the ghost and then pretty much trained himself in at least the basics.
Edit: I guess I should add that if you are only interested in the having force powers part, skip the first Dark Forces.