Tap the Flashlight (torch) icon to toggle it off.
Alternatively, use the power button shortcut (if enabled) or ask your voice assistant (e.g., "Hey Google, turn off flashlight").
Open Quick Settings by swiping down. Tap the Flashlight icon (usually a torch symbol) to turn it off. If not there, swipe again to see more icons. Alternatively, some phones turn it off by pressing the power button.