SO MUCH easier just to find some great dog classes in your area, attend once a week and then get some structure going in your pups life.
Dog classes are a blast! Socialization, exercise, mental stimulation. Amazing how much more fun a dog is when they start to learn, bond, and WE get the skills we need to get that going. Not the dogs fault that your dad bought it thinking it would only need time/attention like a plant or fish and instead it's not just a 'dog' but a GERMAN SHEPHERD!
Good luck and update us with your classes and how things are progressing.