The best way I know to stop a dog from peeing on furniture is take him outside after he eats. Make sure he "goes" before he comes back in. If he is doing this while you are not home. he may not be getting enough attention or potty breaks. If he is doing it while you are in the room, firmly tell him "No" and then take him outside so he understands outside is the place to pee.
To stop dog from urinating on the furniture, get the dog neutered if he isn't already. A lot of male dogs will urinate on furniture in an attempt to mark it. Take the dog outside after he eats or drinks, and reward him thoroughly when he does his business outside. If you catch him urinating on the furniture, say 'No' and take him outside.