My GSD male is 2 and 1/2 months. He doesn't bark at anyone and goes to everyone who ever approaches him. He goes wags his tail and starts licking them or moving around them. he only shouts some times at us(family members) when we play with him or when is not getting what he wants.
I want him to bark at new people and not be friendly with everyone. I never tie him inside the house. only time i use lease is when i take him for a walk.
Kindly advice as to how to make him bark at new comers.