I figured out how to play it:
You must complete your tasks as it's said, then stay safe. The office isn't safe, the doors don't work properly.
Your power will run out at some point theres no way to know, but you can recharge it at the toilet.
When u have completed the tasks and the message that your shift is over pops up, go to the door but make sure no girls are following you bcuz if they get you while door is loading you loose.