I dont know what to do with my cats:(?

you can try to re-litter box train them. Give them a treat every time they use the litter box...theyll start to think that every time they go in the box they get a treat so they will start going in there more. you should ad more vertical space aswell. cats need to be able to get around the room without touching the ground. you could ad a cat tree or a shelf on a window sill. They wont need to mark there teritory any more. even tho they are neuterd they are still teritorial.