You really should create your own independent post instead of posting inside an unrelated post. In any case the flashlight is not an app, it's a button on the quick setting panel. Pull down from the top of the screen and locate the flashlight icon, press it on when you want to use it and off when you want to turn it off. I cannot tell you the location on the panel, since everyone arranges their panel(s) differently, according to their most used features.
