Aloha Susan, welcome to BYC and congratulations on being adopted by a chicken family lol. What island are you on? Kauai, same as me?
My advice is that there is probably no real wrong food that you can feed them with the exception of citrus and avo but they will naturally avoid those. Also, think proteins, as that will be the best bang and welcomed by mom and babies, the carbs will take a chicken a long way too.... and greens. We live on green islands so chickens have lots of grass to munch on but would never pass up an old salad from you -Basically any and all table scraps, heavy on the protein, they love bone meat. Since you enjoy them, you may feel good about purchasing some "scratch" from a feed or hardware store. Feed stores will have smaller bags that will be more manageable at an apartment. And always leave them a dish of fresh water. That will be very appreciated by your new little family. With that said, you are probably going to make the bestest friends that you ever had-unfortunately no one else in your apartment building is going to be happy about it. See if you can't take their meals a little further away from trouble if you need so you don't get sad when someone traps them and ??? Most people think our junglemix a nuisance.
I hope you check back in with us and let us know how you all are doing. We love photos here on BYC!!! Stay well, Aloha, L.