Is your dog barking and growling at *xyz"? The first step to fixing it is to
AVOID SITUATIONS THAT PUT HIM OVER HIS THRESHOLD
Do not just stand there and watch or scold but actively retreat until your dog is calm enough to accept treats.
Every time your dog crosses his threshold he becomes worse.
Moving away should always be the #1 thing you do with an over-the-top anxious/stressed/reactive dog.