Don’t worry you’re not asking too much questions!
First off, what kind of litter box are you using? And what is on the floor of the cage or what type of flooring is it (if there is nothing on it)?
A good way to encourage rabbits to pee in the litter box is soaking up some of their urine that they peed outside of the litter box and put it in the box. Second, scoop up poops and put them in the litter box. Wipe down anywhere he has an accident with a vinegar and water solution. Training can sometimes be difficult until they are altered, but don’t give up! He could be marking his territory with the poos. Keeping up with cleaning up messes as quickly as possible is tiring but it really pays off. Personally, I use Yesterday’s News as a litter.
As for chewing your clothes, whenever he does, push him away gently and say “No.” not harshly, but in a firm tone. Or you can try clapping or squealing high pitched. It will take a few times, but eventually they get the hint. The best way to deter from chewing on furniture is to provide lots of safe chewing distractions, i.e. cardboard, untreated willow baskets, untreated timothy or sea grass mats, phonebooks, apple twigs, dried pinecones, untreated soft wood blocks, ect. When you see your bunny chewing on furniture, again say “No.” and try to redirect their attention. Vinegar or strong smelling perfume also helps sometimes.