Where are the spark plug? Or do I only have ignition coils?

You have spark plugs and coils. If the light is on do not assume it's one or the other. You need a proper diagnosis that starts with a system scan and identifying which cylinder is misfiring, if there is a throttle fault, a false sensor reading, etc. Use this link to find a good shop near you. https://repairpal.com/repair-shops Alex