Hello pectrolyte and welcome to the forum.
Feeding is not an exact science and it will vary from dog to dog. As an estimate I would feed a puppy only a top rated puppy food and would give them one cup (just a little under 250 mil) three times a day.
Don't worry about bulky muscles, training or any major exercise. Let the pup mature and finish growing and bone forming before you consider bulking it up.
We would enjoy seeing some pictures of your new boy. What is his name?