I can't find the episode from Twilight Zone It was about a negect little boy who find a old man across the road and finally he was born to another parents?

The episode you're referring to is likely "The Changing of the Guard" from The Twilight Zone. In this story, a disheartened teacher reflects on his life and the impact he has had on his students. He encounters a young boy who represents the innocence and potential of youth, ultimately leading to the realization of his own legacy. The theme revolves around the significance of guidance and the interconnectedness of lives across generations.