He could have force projected himself all over the place and intervened in various affairs in the galaxy.
Maybe he learned some cooking skills, like how to make the most unsavory tasting dishes from roots.
Maybe he picked up a book or two and learned how force healing works, since he flunked that course previously in his Jedi training.
He could have invaded Palpatine’s mind and tormented him with “yo mamma” jokes all day, just for fun.
