My family and I are flying to Italy. For carry on-s, can I bring a small duffel bag and a backpack or is it just one or the other?

U can bring 2 +2 that is 2 checked and 2 carryon including the laptop bag

Agree with the previous post that you can bring both as long as one of them can fit under the seat in front of you. Most of the time, there would be no question, but on some of the international flights they do tighten up on their rules.

Most airlines allow one carry-on and one personal item per ticket... If you can fit your backpack under a seat it should qualify as a personal item. my personal item is always a small backpack. Also your duffle should meet the size requirement , you can find it in airlines website