get a socket set to start with, some spray-on oil, a haynes manual and if you feel flush a parts manual, download the official workshop manual for free and as long as you can read and can move your hands, you'll have no problem.
get an old 90 and without even trying you'll end up with some mechanical competence.
I barely could put fuel in a tank or check oil, then I bought an old 90 and with no training whatsoever, and all the above books, I'm rebuilding it entirely from the ground up - as well as changing and adding a bunch of stuff that 6 months ago I'd have thought was witchcraft.
PLUS, if you get stuck, theres at least one person on here with a smattering of helpful knowledge.