It is too young to be out of the nest; otherwise it is probably fine.
Haven't you been attacked by the parents when you go near it?
The best recommendation is to put it back in the nest. The parents don't care about your scent on it - only mammals care about the scent.
To find the nest, walk around nearby and see when the parents get most aggressive about attacking you. They won't actually hurt you - that looks like a mockingbird. The more they attack you, the closer you are to the nest; It's probably in a tree. If you find the nest, make sure the baby is warm, and then put it back in.
If you can't do that, make a nest - a box with some bedding in it, that the baby can't fall out of, and put it in a safe place where the parents can get at it. It will call them when hungry, and besides, they are watching. They will care for it until it is fledged - not too long now. They will feed and protect it after it is fledged too, after it leaves the nest, until it can catch its own bugs to eat.