Let the dog outside to do his business, first. Puppies tend to have accidents when they get excited. Make sure that your puppy is supervised at all times until he is house trained and obedience trained. This will do away with a lot of frustrating accidents. Think of your puppy as an infant.
Supervision is the key.
Puppies need to eat more often than an older dog. Check with your Vet to find an appropriate feeding schedule for your dog. I know that it sounds like a lot of work to have a puppy, and it is but trust me when I tell you that it doesn't last forever. A puppy can start basic puppy obedience training at about 6 months of age. Check with your local shelter for the recommendation of a reputable trainer.