No, don't give him puppy food that is not large breed puppy. Many people on this site don't even feed puppy food. Where did you go for food? Besides Walmart and the like, I only have a Petco, Tractor Supply, and small pet store. I've been feeding Stormie Blue Wilderness Large Breed Puppy. She used to love it, but not so much anymore, so I am transitioning her to Fromm Large Breed Puppy.
You can feed an adult food as long as the calcium is low. Blue Buffalo, Taste of the Wild, Fromm, Origin, and Arcana are the most recommended foods that I have noticed.
Stormageddon (Stormie) GSD 11/9/13
Rio Husky/Shepherd Mix 8/1/00-7/15/13