What would the estimate be to replace driver side front headlight and spark plu

What is your question?

My car won't go the speed it should, i press on the gas but it seems slow, also the front driver headlight is completely out should i replace both?

What makes this problem better or worse?

Well i need a headlight at night and my car stutters when i try to start the car.

How long has your 2015 Volkswagen Jetta had this problem?

The light about a month, the spark plugs thing started this week