The outermost lights are the low beams, the next set towards the middle are high beams, the next set are "fog lights" (not every car has them, so they may be very small running lights), and the inner most set should be the turn signals.

If your headlights only come on when you turn on the high beams, most likely your low beams are burnt out. There are instructions for replacing them in the owner's manual, and it is a very simple process (other than the space being a little cramped for getting your hand in there). I've done it many times, and once you're used to it, it can be done in just a few minutes.

As for the fog lights... I would verify that your car is equipped with fog lights, since as I mentioned before, not all cars have them (mine doesn't, but a family member's does). There will be a secondary switch on the turn signal lever for fog lights if they are available on your car.

 

Tell me about it... With a bit of pushing stuff around behind the passenger side headlight (i.e. the wiring harness which is tight against the back of the headlight housing and the fill tube for the windshield wiper fluid) you can create just enough room to get the back off and access the bulbs.