I just got a dog and she barely eats. She selects what she eats. She is very playful but I am not sure about how to care for her. I need assistance about that

Are we carnivorous by nature or is this built in by habit and society throughout the ages? We can survive perfectly by eating vegetables and plants alone. Milk and eggs should also be aloud. Just the exception of meat from animals. I think we would do just fine and that we definetely NOT need meat in our daily foodprogramme. I even think I can go a little further and say that we would probably be more healthy if we stopped eating meat. Good for karma AND good for body.