Says they mainly eat insects. So you may have to go to your local store that sell fish bait and buy crickets or live meal worms. I’d also go on the ornamental forum and talk to those who keep wild breeds.
I’d put a mirror in with it and raise it with your ducks when it’s old-enough to be outside, once it’s mature just give it the choice to stay or leave. If it’s a migratory bird it may leave on its own. Sure is a cutie oh an a stuffed animal or sock for cuddling