Chapters 10 and 11 in Blair Witch take place in the sawmill. The road to the building was long, but it will bring you closer to truth. The following page contains a walkthrough for both these chapters.
Enter the sawmill territory and activate the generator. Thanks to this action, the lights around the complex will be activated. Come in through the only open door. Before that, you can also call Jess. Inside you will find a photo and another tape.
Go outside and play the tape. Stop it at the moment when the person on the recording opens the second door. This way, you'll get access to the room in the middle. The middle drawer contains the code for the padlock.
Go outside and proceed to the gate with the padlock. Set the latches according to the code and climb upstairs. Approach to the screen, unveil it and look at the person lying there. After returning to your senses, pick up the tape lying next to the body and watch it.
Now, approach the window. You will see a man playing with Bullet. You have to confront him.