So the wiki has no mention of the skill system, gaining experience for skills, leveling up, or what the skills or level actually do for your character. If anyone could explain the system or usefulness of these I would greatly appreciate it.

Also my treasure hunting skill doesn't seem to be gaining any exp. I've found at least 30 treasure chests & farmed the first two bosses for crystals a ton and the little exp bar is still empty. The only thing else I can think of is fishing, but I don't have a fishing pole. (not sure if you can craft one or you have to buy them)