[cypher]

I'm not quite sure which bits on the cage you mean he's chewing but if there are little bits of plastic he can get too then he's probably just chewing them because he can! Lots of enrichment to keep him busy will usually help with most chewing issues, try giving him a whimzee dog chew (most hams love them) & scatter feed rather than using a bowl.
If you can post a photo of the cage & where he chews that would help.

A little bit of nibbling is quite normal to begin with, if you just persevere with hand feeding they soon get the hang of what's food & what's not, the nibble things to explore & that can include hands at first, they do usually get over it quickly enough though & putting a sock over your hand won't help him get used to your hand & scent which he needs to do.

Have you got a playpen (escapeproof!),or a large enough safe play area where you can interact with him out of the cage? Some people use the bath with a towel in the bottom & some toys to explore in there.
Start getting him out for a short session each evening, he may be a little nervous at first but as he gets more confident you can keep him out for longer, sit in with him & he'll probably want to climb on you & just run around giving you the chance to interact & get him more used to handling, go at his pace, don't try to rush things & he should be fine.