"In general, try things that seem worthwhile, set goals and work hard to achieve them, and see where that leads and how you respond. It’ll be clear when something becomes compelling"
Everybody says "do what you love". Few say how to find what you love. Fewer still say how to manage to work as hard as you should to find what you love.
It's kind of a circular problem, when you love something you'll naturally work very hard on it, when you are still searching what it is you love, it's really hard to get the energy to work as hard as you should to find the elusive loved mission.