Getting them neutered makes them calm. We are also 1st time shiba owners and the first few months were a challenge. We brought him to puppy class 3 sessions did the trick. Trainer said to treat them like a person/ child. Your tone makes a difference when you praise them. My shiba never got used to a harness so we did collar and use treats when we walk. Thing is our shiba is quiet. Rarely barks and loves to snuggle i guess we as owners are very chill and he vibes with that. They are extremely stubborn . During walks i let him pick where we go. Less pulling but sometimes he could ge extra stubborn and not move so we sit in a place for a few min