Briefly, Jesus outlines the calling for every Christian here:
Mark 12:29-31 ESV Jesus answered, “The most important is, ‘Hear, O Israel: The Lord our God, the Lord is one. (30) And you shall love the Lord your God with all your heart and with all your soul and with all your mind and with all your strength.’ (31) The second is this: ‘You shall love your neighbor as yourself.’ There is no other commandment greater than these.”
This isn’t a very specific answer, but it’s a very significant one.
It’s in response to Jesus being asked what the most important part of the law is. Why would somebody ask that? Because they’re hoping to trip Jesus up or they’re hoping for some sort of permission or endorsement of their current way of life. In the case of the Israelites of Jesus’ day, they were looking for laws connected to overthrowing the Romans or perhaps gaining public honor through religious ritual (Matthew 6:1-18).
But the most important thing, before you start looking to do some “world changing” or “personally enriching task” is to learn to appreciate God and to bring well-being to your neighbor.