If he can find his food, but not his water, there might be somethign wrong with him, he might be ill. PLease take him to an avian vet.

Meanwhile, you can get a little dropper, and put a drop on his beak so tha tit drips down and he can tilt his head to let it go in his mouth. one drop at a time. Slow. If he doesn't drink, take him to a vet immediately.