It's a Chevy HHR 2006 and I don't know what to do. First one low beam went out now both are not working but both high beams are working. What do I do?
This is most likely blown bulbs. Each bulb has 2 filaments in it, one for low beams and one for high beams.
Since the low beams failed at separate times and the high beams are still working, it is less likely you have an electrical fault, and more likely the bulbs failed because they were from the same production line, same usage stats, etc.
You local auto parts store should have an applications guide to tell you which bulbs are the correct type for your application.