I dont know whats wrong with my car

I had. the same on my Laguna it was the piston rings on mine.

I'll go with blown head gasket as well, it's blown between cylinders allowing combustion gases to flow between them causing the severe misfires. Should check your coolant and oil, as you might be seeing some cross contamination. If you keep driving it you'll turn this engine into a boat anchor, if it isn't already.

Check to see if the engine coolant is low. Loss of coolant without a visible leak and dense white smoke indicate a head gasket or cylinder head problem.