What path should I follow in order to understand early on whether I have oral cancer? Do I need to see a dentist every 6 months?

See DDS. Have your dentist perform an oral cancer screen, if problematic you may be referred to an oral surgeon or MD.
Only. Only if you want to remain healthy. Your Dentist has more than 10,000 hours training, years of experience, and an office full of sophisticated equipment designed to help the Dentist keep you healthy. Periodic Dental Examinations allows the Dentist to activate all these systems to your benefit. Between examinations don't smoke...anything. Don't abuse alcohol.
Several choices. Seeing a dentist is a good start. Dentist do physical exam,s surface, incisional or excisional biopsies. Self examination for new growths, ulcers or sores, changes in color, firmness or contour of soft tissues. Dentists often refer to oral surgeons or oral pathologists for further evaluation. There are also many conditions which mimick cancer but are not malignant. Regular visits a good start.
Oral Cancer. Oral cancer rates at your age are rare, approx 1 in 125,000. Rates go up with tobacco use, and rise even more with drinking while smoking. Oral cancer can be painless, and physical changes may not be obvious to the untrained eye. Any lesion that has not healed in 14 days should be examined. Visiting your dentist every six months is always a good idea. http://oralcancerfoundation.org/facts/