Just want to ask: first level? You have just finished the first level and you have possesion? How? That is a late game power. You should invest in some other more necessary power like Blink or Dark Vision. If you have picked that power, then it is sure you don't have Dark Vision or Blink tier 2. You need more than just one power because that is when you will have more things to do, you can combine them with other powers and gears to make carzy things. The game allows you to do whatever you want and there will be consequences for your actions, your every actions.

Keep playing, if you only get the first mission and already complain about the game, I think you haven't had much experiences about how to enjoy a game.

I have finished this game with no kill yesterday and, while limiting myself to the non lethal path and try not to be seen at all have made me unable to perform some bizarre ways to finish the quests, I still find enough to really appreciate the devs for making such a lively world with so much things to do. Try to think for a while before doing something, there is always another way to do it. The freedom to do what I want and the results it can bring is really fun

And FYI, if you think I haven't played enough to say anything, I have been playing this game for more than 20 hours, trying to do everything, gather everything, read most of books while being completely unseen, on hard. Will try on very hard tonight, but with some killing.