What animal hunts beyond its capabilities? An unsatisfied one. The successful ones do what’s easy, simply fulfilling their innate abilities.
So how do you know what to do with your life? Whatever comes easiest to you. You’re provided a particular disposition and preferences, along with particular abilities — these form a map, a pathway to what you should do.
Your path may appear difficult or unpleasant, but it’ll be the easiest and most pleasant option when compared to alternatives. People around you, or even the bulk of society may not appreciate your path, but you must press on. Adopting another path is not an option because your natural tendencies will always pull you back.
So when looking for your life’s role, do what’s easiest, what most closely matches your preferences and abilities. To those on the outside, your role may appear heroic, even impossible, or it may appear aberrant, perhaps evil, or it may simply seem mundane and repetitive — but this is your role, not theirs. Your role may endure, or it may end abruptly — observe with patience and acceptance, and if possible, appreciation.