Corgis are the smallest large breed dog. For your puppies complete nutrition, feed them large breed puppy/dog food. This should be fed until your puppy ins 12-18 months old. A starved looking corgi is a healthy corgi. They are very food motivated, making training a breeze but over treating can lead to overweight.
Table food should never be acceptable! It brings no nutritional value and can be harmful to your pups life.