What to feed and do with a baby bird fledgling?

You need to contact your local bird rehabilitation person before you kill it with kindness. You are not equipped to properly care for this bird, and if it has no bird around to teach it how to find food and fly away from predators it will have no hope of surviving in the wild. google "bird/wildlife rehabilitation" right now if you want to help this bird, and next time do not interfere with mother nature!