This is a quest, worthy of a life. As Peter Drucker said so many times, it is the ability to say "no" that makes a person effective. It is only in the "no" that you are exercising your discernment that, "this" (whatever it may be) is not for you. It is not where you can make a significant contribution, it is not where you can make the biggest impact, it is not where you can be your best, it is not where you can change the world.
The primary marker of the modern world is choice. And the closer you are to the Western Core of that modernity, the more choices you face. My wife and I have live abroad for the last 20 years, and some times that included very remote places around the world. There are few choices in those places. But in the technology heavy West, the rich rich West (regardless how poor those citizens feel and profess to be) they have an overwhelming number of choices. The most powerful among us are those who learn the skills to say "no" and to separate the vital few from the trivial many (this phrase as well as these core ideas, I took from the book 'Essentialism" by Greg Mckeown).
This requires a number of disciplines, not the least of which is self confidence. Self confidence of a nature that allows you to stand in the face of immense social pressure. You will be choosing a far less trodden path than the many will be following. This level of self confidence is the product of mental and emotional discipline, and can include scholastic or experiential or spiritual disciplines as well. It also needs a risky heart, that is determined to maximize this one short life while it is mine. Are you choosing the vital few, or the trivial many? What do you want to change in the world? What or who do you want to liberate from bondage? Where can your highest contribution be made? What inspires you? What need does this world have, that I possess? Can you resist all the noise of the trivial many, and identify the vital few objectives/tasks/goals/abilities/competencies/needs/ that you want your life to impact?