I can't see in the dark as well as others can? Do I need carrots or vitamin a?

Vitamin A. Vitamin a is in many foods, including carrots. Night blindness is a manifestation of severe vitamin a deficiency. Ingesting vitamin a in healthy foods is worth doing for everyone.
Can't hurt to eat... Carrots, but probably will not make a huge difference. See an ophthalmologist (eye doctor) to make sure your eyes are okay. Only relationship between extra vitamins and eyes is for possibly slowing progression of macular degeneration, an eye disease. Try eating more fish high in omega 3 fatty acids. May help.