@Rincewind
Some house rabbits can be really destructive; the best thing you can do for them is protect the stuff that's either really important to you (walls, baseboards, etc) or dangerous to them (cables, etc) with barriers of some sort. Finding alternate things they're happy to destroy instead of your Good Stuff can help - cardboard or paper, nontoxic chewable pet toys, grass mats, etc.
Others are hardly destructive at all, and will only chew on things you give them. We've had a couple like this. Unfortunately they're not the majority 😉
A large enclosure is good, but it's better if you can let them out to roam, at least part of the time (like when you're in the room). If the room or rooms they have access to don't have a natural barrier that stops them, you may find a baby/pet gate helps.
Depending on the flooring where you have the rabbit and how destructive they are, you may find a cheap big carpet from Walmart or whatever is a good investment. Many rabbits dislike hardwood, vinyl flooring, and other slippery surfaces, and won't get the exercise they need if they don't have something grippy to roam around on. For others, it can let them chew on the cheap carpet and not the expensive wall-to-wall good stuff underneath it.
I wish you all the best with your new vegetarian housemate. Keep #HouseRabbit and #RabbitsOfMastodon tags handy if you want to ask for more info from us rabbit servants.