This thing has been with me for more than 3 months, and I went to the doctor, and she prescribed me a burning cream, but it did not improve
anu answers please 
It’s hard to see what you took a picture of and where exactly it’s at. Do you have a better picture?
It’s at the entrance to the vagina, right at the opening
It’s too far zoomed in to see. What are your symptoms? Is it painful and swollen, like a cyst? It could be a Bartholin Cyst.
no just red and bit burning when i touch
I’ve never heard of “burn cream” for inside of the vagina. I would get a second opinion from a different OBGYN.
yes 
Have a new OBGYN do a PAP, full screen STD test (including blood work) just to rule out anything like cancer, stds and infections. Maybe there’s an infection irritating you, or a cyst under the skin that needs to rupture. Just see a different doctor this time. I’m sure they’ll be able to help.