Hi Nancy,
It’s good that you brought the bird inside to keep it safe. However, this bird is protected by Federal & State laws, so it is illegal for you to have him. You must contact a wildlife center or rehabilitator so you can turn him over. The bird needs medical care by a wildlife vet, and then it will be released back to the wild where it belongs. The longer it goes without treatment and proper diet, the less likely it is for it to survive. This is not a pet, and if a game warden seizes it, you will face Federal charges and steep fines. As for feeding it, do not try to force feed it. You can put a dish of water in the cage and some soaked cat or dog food. This is only temporary, until you find a place to take it. Do not give it chicken feed. Here is a link to help you locate a wildlife person.
https://www.nwrawildlife.org/page/Found_Injured_Wildlife
Thank you for helping wildlife,
Brenda