I have a cut type thing on my right vagainal lip next to the vagainal entrance I don't know what it could be or how to heal it I had a baby in August and have chronic UTIs and got tested for everything last jan have not had sex since and have no stds need help

Is it red, inflamed? Is it open? Can you look at it with a flashlight and a mirror?
Generally keep open skin as clean as you can, dabbing with lots of water and just a tiny bit of very mild soap, and rinsing well, and pat dry without rubbing. You could buy some antiseptic wipes and spray. Air yourself out on your bed for a while each time you wash, and wash as often in a day as you can for a while. Wear white cotton undies and loose clothing. See a doctor if it doesn't improve, a rash develops on surrounding skin, or you get a fever.