[Maybe the problem isn't that Ky has too much spare time, maybe he simply hasn't formulated the right things to do to fill his time. Clearly cooking is a skill that many people have that he lacks -- although he's not sure it's one that he can really obtain, since he recently tried and the fact that Sol lives above him makes him even more self-conscious than usual when Ky starts to be making his own smoke.

It has become clear to him that simply taking up more patrols with the Defense Force isn't ideal, and he can and has exercised but even that leaves him wanting something more.

And, well, why not? If he ends up not remembering or retaining anything from here then it's not really a loss, and if he does gain a skill then it can help him.]

What sort of things have people been able to learn that they consider useful? Not so much magic that can't be taught, but, for instance, how to stitch a wound, or fire a bow?

You don't have to be able to teach it...although I suppose it would help me if you could and were willing to.