Why dont all birds have the same type of beak and feet?

Most birds, as with most other animals, have biological features that have adapted to their environment. For example, a bird who eats buts will have a thicker, shorter bill for breaking the nuts while another bird like a woodpecker will have a long think beak for poking and grabbing insects and bugs out of small holes. Feet differences are adaptive traits as well. Examples are the webbed feet of waterfowl which allow for greater proulsion force in water or for the long legs of stilts to keep their body out of water while they wade in water for bugs or small fish.