Hi i am a 19 yr old boy and i masterbate a lot around 3-4times a day and almost everyday .will that pose a problem in future wen i have sex??

Probably not: Masturbation is a natural activity and not affect later sex life. The only time it is actually a problem is if someone spends so much time masturbating and doesn't go out to meet other people and pursue other relationships. Occasionally, frequent masturbation can cause you to be sensitized so that less stimulation is not enough. Stopping your self-stim for a while usually solves that.