When i open my mouth the back right i see a white lump its not an abscess all my teeth are rotten it look like a tooth could it be a wisdom tooth? or like oral cancer?

Hard to say: When it comes to questions like yours, ones that ask for a diagnosis, it is better off examined locally by a trained dentist. Please call a local dentist for an appointment.

Can't see: Without an examination/imaging/lab tests there is no way to arrive at a diagnosis. If your teeth are "rotten" that infection is spreading through your body and damaging other organ systems. Please see a Dentist NOW.