So a slum dweller goes through life and struggles against all sorts of personal challenges, generally caused by other slum-dwellers and "bad" types like mafia gangs.

But along the way there are crucial details that he encounters in these major events in his life and these details provide him with the answers he needs to be able to win Who Wants To Be A Millionaire.

The movie is told in an episodic way retrospectively.

Of course the protagonist in the story is a small-time hero and he is virtuous in how he goes about his life, as opposed to virtually every other slum-dwellers and "bad" member of society.

I've already put this in a different comment but the thrust of the story is that virtuous people will be rewarded by fate and that slum-dwellers (i.e. everyone in the slums besides the protagonist) deserves to be there because they are "savages".