Here’s another way to look at the intersection between story and character.
All stories take place at the transition point between one stage of human life, and another stage. The transition between childhood and adulthood, immaturity and maturity, innocence and experience, psychologically damaged and psychologically whole.
Every protagonist is poised on the edge of that change from one version of themselves to another version, and your story is what’s going to push them there.
Sometimes the transition is negative and the protagonist is resisting it. A man whose wife has been kidnapped stands on the boundary between being a husband and being a widower, and understandably, he doesn’t want to make that transition.
More often, the transition will be positive in the end, but the protagonist is naturally resistant to change. Because in the end, aren’t we all? Change is weird and scary, and we aren’t sure we’re going to like what we might become. But change is the only option your protagonist should have, and your job is to keep pushing them down that slippery slope until they embrace it.
So define what stage of life your protagonist is currently in, and what stage you want them to end up in, and you’ll be a step closer to defining how your story will get them there…