Consider the Bible verses at Eph 1:3, 4: "Blessed be the God and Father of our Lord Jesus Christ, who has blessed us with every spiritual blessing in the heavenly places in Christ, just as he chose us in him before the foundation of the world." God knew you, you see, before the world began.
In Matt 10:30, it says that "the very hairs of your head are all numbered." In some translations of the Bible it says the hairs of your head are all counted, but in the King James Version of the Bible it says the hairs of your head are all numbered. So you can't comb your hair in a morning and a couple of hairs come out in the comb without God knows about it and has allowed for it. That's the measure of his concern for you.
Now look at 2 Tim 1:9. "Who has saved us and called us with a holy calling, not according to our works, but according to his own purpose and grace which was given to us in Christ Jesus before time began." Not only did God know us before the world was created, but He both had a purpose for our lives and gave us the grace to fulfil it, even then.
Finally, look at Eph 2:10. "For we are his workmanship," it says, "created in Christ Jesus for good works, which God prepared beforehand that we should walk in them." God has prepared things for us to do, things that no one else on earth can do but us. Every one of us has a gift, a ministry to fulfil. I often think of Dorcas, who was "full of good works and charitable deeds which she did." When she died, "all the widows stood. . . weeping, showing the tunics and the garments which Dorcas had made while she was with them." She might not have been a great preacher, but she had a ministry, something given her to do that would bless others and affect the world for good.
It's a sad thing, but many people never find the ministry that God has for them, because all their lives they make their own decisions and go their own way. If you want to find God's purpose for your life, repent of your sin and yield your life to Christ. Then He will begin to lead you into a life that is fruitful and wonderfully satisfying.
Perhaps you are a young Christian, and you have not yet found the ministry that God has for you. Don't worry. Pray. Read the Bible. Join a Bible-believing church. Begin to do the things that are at hand for you to do, and be faithful in them, and God will lead you into the life He has prepared for you. He will not fail, for He is faithful.