The following page will tell you where to look for the flashlight. We indicate the exact location of the item and instruct how to use it.
You will find the flashlight while searching for one of the Transmitters, near the corpse of one of the crew members. The picture above shows you the location of this place.
First you have to cut the rope that the corpse is tied to. Go upstairs and cut the rope with a knife or a tactical axe. Go downstairs to collect the items from the body.
The flashlight is right next to the corpse, on the left.
The flashlight requires batteries to work, which you can find in the game world while exploring abandoned camps and caves. Open the inventory menu by pressing the I key, right-click on the flashlight and do the same with the batteries. Then left-click on the gear icon. The flashlight will be ready to use until the battery is discharged. Then you will have to repeat the whole process. More information on combining items can be found on the Crafting page.