Hello. The location of the engine number should be under the hood or on the top of the metal railing where the hood latches to when closing the hood it self.
It entirely depends on your model of car, but usually you don't need anything special. Most headlights can be accessed from underneath the bonnet in front of the engine. Wear gloves if you have them and avoid touching the bulb with your bare skin to avoid getting grease on the glass. Example videos can easily be found on youtube (such as VW video attached).
Also is your Coolant or oil level low after driving? Does your spark plug look like there is lots of white or black deposits on it? These indicate mechanical problems in the cylinder.
what is the question
what is normal, answer , mostly weight and speed of right foot.
what is mine. (google it, 1000s there)
is yours bad>? not stated yours.