sure, you can. It’s fiction.
Could it be done? Yes depending on range etc. If I were chosen for that mission I would want to make certain everyone was comfortable with a head splat because the chances are pretty good that would eb the outcome.
It is the target’s movement that would make things complicated, as a person walks they not only move laterally they move vertically and that is where things would get complicated.
Depending on distance, bullet, powder charge etc. the time form firing to impact would make it tough. If you could get the target to stand still for a few seconds it would be a no brainer, again depending on distance.