will a male after continuous masturbating for 15 years became a father in future when he marry?

Yes of course! There's nothing wrong with masturbating. In fact, masturbating actually lets your testes make new sperm, so you'll be more fertile :D

Only if he has sex with a girl and she is fertile at the time. Certainly masturbation won't impact fertility of the male. Just solo sex, same physiological act as sexual intercourse. You never run out of sperm, you continually produce them all your life.

Continuous for 15 years !!!.

You mean no sleep ?

He needs to have sex to become a father.

Yes. I've been jacking-off since I was 3 years old and so far, nothing bad has happened.

for 15 years, day in, day out? you will have some serious problems

It is no different than having sex with a female.

its unlikely he will ever marry at that point

what