You didn’t say how old your bunny is, but it’s usually recommended that you don’t start feeding greens to a rabbit until they are 12 weeks old, then do so gradually. Try one green or veggie the first week, then another one the next week, etc. You can find out which ones they like the best and which might not agree with them. Click on the BUNNY INFO link at the top of the page, there is a lot of good info there, including diet, with list of good veggies. Make sure that your bunny is eating plenty of hay.
If those wood shavings in the cage are pine or cedar, those are not good for rabbits. You can use aspen shavings. It’s really best not to have bedding all over the bottom of the cage, but just to have bedding or litter in a litter box. Although, it is not always easy to litter box train a rabbit before it has been spayed or neutered. If that is a typical pet store cage, it is probably a small one, so your bunny needs out of cage time every day, for play and exercise. You do have to “bunny proof” any rooms that he is in, as most rabbits are bad chewers. The BUNNY INFO link has info on bunny proofing.
Mr. Loppy is very cute!