2006 hhr smelled smoke. white smoke came out under dash. now it wont start.?

This could be many things like a bad ignition, shorted wire and burned up relay. In this case I highly recommend disconnecting the battery immediatly and getting the car towed to your local shop. This is very dangerous depending on what it is. Best to be safe. Use this link to find a good shop near you. https://repairpal.com/repair-shops Alex