He’s honestly just being a bunny. Bunnies chew and dig things. Mine constantly scratch and dig at the hardwood. Keeping him in his cage will only make him resentful, as he doesn’t realize he is being punished. A lot of people want to squirt bunnies to train them, but please don’t do that, because again he’ll recognize you with fear. You can spray bitter apple spray, not soap, around baseboards and other areas you don’t want him to chew. Soap can be very harmful and toxic to bunnies. Bitter apple spray is a non-toxic deterrent. To help him chew you can leave out hay toys or cardboard boxes as a chewing alternative. For digging, you could make him a digging box out of sand or scrap papers or something like that. Also laying out fleece for him to dig on is a good idea that my boys love.
He’s also at that age where he could start losing litter habits soon due to his hormones, just as a warning. Using vinegar is a great way to get rid of the smell and stain of any markings. Hope this all helps 