First of all, we cannot know the mind of God, nor His Will. But be not discouraged, because we can know His heart. Therein lay the secret to life in Him. As we surrender all and abide in His Son, Jesus Christ, we become one in heart with the Father, Son & Spirit. Yes, it is a mystery, but one of Truth and Love that we can "know" and experience in our heart and soul. As we spend time in His Word, seeking Him in quiet, His Spirit will begin to transform us, and He Who begins that work will see it to completion as we abide in surrender.
So then, you ask, "What next, what is my 'ministry'?" From experience and age, I have this simple question in reply; what do you wake up to each morning? Wife, children, roommates, just yourself? Begin there first of all. Get that wrong and you will not "be" in His Will, nor one with His heart. Then, what or who is immediately outside your door, in your neighborhood? Go there with an open heart and mind seeking Jesus; neighbors, institutions, businesses, people in all those places, especially the ones you hesitate to engage; homeless, dirty, odd and even a bit crazy.
There you are, not "rocket science" or deep theology, just LOVE.
One last recommendation, seek wise counsel in trusted mentors and disciples. The road will be more smooth as they help you "see and hear" God. The true ones will simply and lovingly "direct" you to Him and diminish themselves in humility.