You will find advice here to help you on your writing journey. Use the search bar to find some of the insights and shortcuts we use to fast track our writers.
'There was a man who... ' This person has a flaw, a failing, either moral (a tendency that will bring them and others misery) or cosmic (a hole in his or her fortune). They can't see it. Well, I can't see mine, but Robbie Burns was right to bemoan the fact that we cannot see ourselves as others see us. It would save us a lot of grief. But a tale is the closest we ever come, like Narcissus, to gazing at our own reflection.
The action of the book sets the flaw straight or shows it in dreadful relief.
At the denouement the protagonist takes one of two paths - he sees it and corrects it or stands corrected, or - and perhaps wonderfully, embraces it. This latter is a very rare outcome (The Godfather is much quoted as one of these, and I do rather like the idea of playing with the usual form.)
So your hook must posit - a person with flaw, and the outcome is this flaw being corrected. That my...