Your pitbull puppy is at 10 months old. Very good that you take him for a walk everyday where he does nothing but play. When yiou take him back inside, he pee! This is not a good thing. Peeing inside is a behavioral problem.
So start training the puppy, you will have to build your routine around your puppy's needs, and these are reliably predictable when they are very young. Puppies need to urinate immediately after waking up, so you need to be there to take your puppy straight into the garden without any delay.
Puppies have very poor bladder control, and need to urinate at least every hour or two. They can urinate spontaneously when they get excited! Be careful of this things too!
Continue this and always go with your puppy into the garden so you are there to reward and attach the cue words to the successful actions! Fortunately, puppies are creatures of habit, so as long as you introduce the garden to your puppy as its toilet area early on, you should be able to avoid most of the common pitfalls.
By this he will be accustomed to pee outside rather than in the house.