After Learning I Was the White Moonlight Supporting Female Character

Looking for Quick Transmigration Stories About the White Moonlight

I'm looking for a story where the male lead's first love is supposed to die young because of the plot, either from illness or an accident, to make way for the female lead. The male lead wasn't in love with the story's heroine in his previous life. But then the first love awakens, or the male lead learns how the story is supposed to go, and saves the one he loves.