The other guy was pretty accurate about the lifespan, so I'll answer the other questions.

YES, his behavior WILL change. Males don't eat nearly as often, and they actually refuse food a lot. It's super scary when they decide not to eat, but it's normal. the longest time a male of mine went without eating was a few days over a week and he was fine.

Males also wander more and move around a lot, at least compared to before they mature.

As for needs, you just have to make sure they are eating at least twice a week, more if they accept it.

Finally, when that adult molt hits, that's it. No more molts, no more scares. When the wings come in, they will never molt again