To care for a bird with a broken wing you have to first mend (bind) the wing with some sort of caste or guaze. Then you give it what it needs such as enough water, food, rest and most of all love.
If a bird has a broken wing it will most likely be seen on the ground and climbing trees. It climbs to a mid portion of the tree to get away from ground predators and hawks that may make a tasty meal...