this mask if you’d like, but you don’t need the mask to be perfect for this effect to work, so a basic shape surrounding them is all you need.
what you can do next is duplicate the bottom layer again 2 more times, labelling each background 2 and 3 automatically. what we’re going to do is mask an area to the right (or left) of the subject in a rectangle and take as much as we can that's just the background and also not cutting into our subject's body at all. then make sure that the anchor point is on the side closest to our subject. when you move the anchor 