yes whole foods is best if you can get them
as you get the bones feathers guts and all the other stuff
which will give a lot of protein and vitamin for your bird
you could always have a drive around
and see if you could find a place where they bread chickens
or just google for a chicken farm
How worrying that you have this bird in your care and you don't even know its dietary needs. Definitely don't feed it pork it will kill the bird. You should be under the guidance of a mentor. Feed the bird rabbit, mice, rats, day old chicks, quail etc. For the sake of the bird find someone that knows what they are doing and go with their advice.