John does not believe that he will get lung cancer from smoking cigarettes, so he does not want to quit smoking. john is in the stage of the transtheoretical model.

He is in the precontemplation stage of the transtheoretical model,where he shows no intention of changing their behavior, and does not see an behavior as a problem when asked.

This matched his case that he does not believe he will get a lung cancer from smoking cigarettes(does not see the behavior as an problem) and does not want to quit smoking(no intention of changing the behavior).

Hope it helps!