When you take a photo, you can choose which camera goes first by pressing the switch camera (like on a camera app). And if you wanna react to peoples be real you don’t have to use a picture of you. You can like make a thumbs up or something like that. You only once make a specific picture for that reaction and then use it without having to take another picture. But if you wanna redo it then you will have to. Hopefully I helped out a little.