Can you give a 3 month old meat?

Of course. Do cut into bite-sized pieces, REMOVE any bones, and best mixed with their kibble. If you do this routinely, the dog will expect it and may turn up his/her nose at plain kibble.

Dogs are omnivores, so if a green bean or two, or other veggies get into the mix, they'll probably eat them too. Basically, if you eat it, so will the dog, in moderation.