When a man life becomes complete Everyone was on a run for their life doing something they don't like. Also there may be no sense of satisfaction in their life. So I am thinking, what makes a man's life complete?

Does the worldly things still matter for a man to make his life complete? Does only meditating makes a man complete? If there is no use in our life then what's reason for our existence. Why we came here into this world? Why are we in this cycle of birth and death?

What is the meaning of life?
The question "why?" with regards to existence comes from theistic thinking. Even some scientists cannot free themselves from this kind of thinking. It is a result of believing that there's some ultimate entity/force in the universe that decides a purpose for us.   

Buddhism doesn't subscribe to ideas like that. Buddhism teaches about causes and effect. It never talks about an inherent purpose or something written in the stars with regards to existence. Because there is none. But that doesn't mean that there are no goals worth aiming for. In an ultimate sense, end of suffering is the goal that is worth striving for. 

If your head is on fire, trying to put off the fire is the smarter thing to do. Not to ask "why me?".