it could be your valves or your engine
white smoke can be either your car overheating, or smoke from an electrical issue
under the hood of your car
If the latch under your hood is damaged and won't lock then your hood could fly up while you are driving. You should take it to a mechanic to see if they can fix your latch.
Most likely it is coolant getting to hot and boiling over, car is most likely overheating. Check for fluid under car, and temperature gauge.
close your hood
By pulling the hood release under the front of the car.
Local car dealerships and auto detail companies may provide under car hood cleaning. For general top of the car hood cleaning, visit a local car wash.
Under the hood of car
under the front of the car.