If it's a crow it will eat almost anything.
It looks like a Starling juvenile but it's hard to tell without lifting the wings. Also the beak is thick like a crow so it's possible.
Tuna is a good idea, contrarily to what many believe, bird seeds aren't very popular among the bigger birds. Sparrows, Chickadees and smaller birds will eat seeds but above that weight class they will eat worms and any scraps they can find.
If it survived the night you can try anything with protein although I'd personally avoid giving it chicken, but cooked eggs are okay. Any cheap canned meat like from dollarama genre Paris Pate will do.
And water.