No, there is no list of unnamed people in Photos iOS. We are not supposed to name each and every unnamed face, as it is not possible to remove the faces of strangers - the would always be cluttering up the list of unnamed people. we should try to find and name just a few photos of the people we want to add to the People album - browse your favourites to find photos of your contacts and name a few of them. Once the people you are interested in are in the People album, you can find more faces by starting from the People album, see: Find people in Photos on iPhone - Apple Support Merge two instances of the same person, confirm additional faces, or correct incorrectly identified faces.
If you have a Mac as well and are syncing the photos between the iPhone and the Mac with iCloud Photos, you can create a smart album in Photos for Mac to find all photos with no named face. Faces you name on the Mac will be synced to the iPhone with iCloud Photos.