I have brown around my gums im very concerned an worried it could be cancer since I jist started smoking 6months ago do u think it could be?

Stop smoking. Brown discoloration to the teeth around the gum line can be caused from staining by smoking and consumption of carbonated beverages, tea and coffee. Medications you are taking and some food can cause tooth stains as well. Stop smoking. Get a dental check and thorough cleaning. Any areas that look concerning can be biopsied.
Maybe. While cancer cannot be ruled out without examination, it is more likely to be discoloration due to smoking and poor hygiene. Some drugs can also cause discoloration so tell your doctor of all medicines, including supplements you may be taking.