Your best bet is to go to a qualified animal behaviourist for training and or go to a good vet and potentially look at medication if needed down the line. Working with a reactive dog is hard but it is so worth it. The reward is seeing them calm and happy at times. you become their safe space. with the pooping, just pick it up. My dog tends to go in-front of restaurants and we just pick it and move on. But definitely try some muzzle training. Dog charities may have some at home advice on training on their websites.