Beginner, please help

I just got this guy from my son's girlfriend. She got it from someone that wasn't caring for it and she knew I would get all the right stuff and care for it. So lay it on me. How bad does he look in terms of body condition and how do I need to fix this enclosure?

I've already read about switching to a sand substrate and I know he will need probably 2 more hides... the only uvb and heat lamp I have on hand is a mini one that I used as a turtle basking spot so I'm setting that up in the mean time.

Food wise, he came with wax worms and a calcium supplement but he does not seem interested in eating. I soaked him in warm water when I got home to make sure he was well hydrated. I can get crickets if that is preferred meal over the wax worms and I know about gut loading. What size cricket should I try for?

Basically, give me the full rundown of what I need immediately vs. What I can order on chewy and get delivered in the next day or 2.