I’ve dealt with 2 puppies. Have lots of treats, go outside a lot and say pee or poo and if he does reward with a treat and say yes. If he has an accident inside, say no and take him outside. You need to get the behaviour right away. Also make sure you get him to the vet if you haven’t already for dewormers and vaccines. Start touching his paws and ears as well, just touch him all over all the time so he gets used to it :)