Why a person of 95 years, who smoked two packs of cigarettes a day
All of his life. Never got cancer of any diseases. If often puzzled me.
Could it be a gene thing??

It very well be, and most likely is, genetic. There may even be other factors such as healthy diet and exercise that contributes too.

Agree

Maybe their parents lived to be 105 :>
Eating a healthy diet
Regular exercise
Good sleep
Being able to handle stress well
Are other factors.

You shoud not take this to mean that it is healthy or inconsequential to smoke.