There is no special app for the flashlight (torch) on the Samsung device. The flashlight can be found under the status bar as a quick setting where it can be switched on and off.

Android 11 | One UI 3.0
How to Turn On/Off Flashlight - Swipe with  two fingers  to access the Quick settings
How to Turn On/Off Flashlight - Enable or disable  Flashlight
  1. Swipe with two fingers to access the Quick settings
  2. Enable or disable Flashlight

Samsung Instructions