Please tell me how long it takes for to get oral cancer?

Please rephrase: How long does it take cancer to develop from what? Naturally (genetic), from smoking, from chewing tobacco? Cancer occurs when cells mutate due to genetic change to cause unregulated cell growth.

Many years : Cancers of the oral cavity usually take many years to develop, so they are not common in young people. Most patients with these cancers are older than 50 when the cancers are first found. Use this time as an opportunity to stop using tobacco.