Is it possible if no one take care of their culture and traditions it can be forgotten?
Behavior and lifestyle will be changed because of modernization.

Sadly, i think that's true. I've been to a couplee remote places where culture once was very evident and talked to the old people there, i've heard sad stories about the newer generation preferring to go to cities and metropolises instead of helping out their villages, so it lies upon these old people to somehow preserve their culture.