Port forwarding opens up ports on your router for other people to connect through. The ports for Unturned are 27015-27017. To open up ports/port forward, you will need to access...
Unfortunately, this means that your game (or console) is defective. If you badly want to play it, you could try replacing the game, or if this occurs with all disc...
Don't Starve requires a lot of practice to get good at. But once you can survive your first year, you should be well on your way to surviving many more.