The most important advice I can give you is to commit these coming days into God's hands, and trust Him to be with you and help you. Part of your concern, I suspect, is a fear of the unknown -- but the future isn't unknown to God, and you can trust Him to guide you as you seek His help.
Let me encourage you to be guided by three principles as you enter college. First, avoid the party trap. As you'll probably discover, many college students find themselves away from home for the first time, and they use their new-found freedom to indulge in all sorts of unwise or even immoral behavior. Even if it puts you in the minority, don't go down that road; you will only regret it later.
Then believe that God has entrusted these years to you. Later, He may lead you into something else -- but for the present, assume that this is where He wants you, and that He wants you to do your very best while you are in college. The Bible says, "Whatever the God of heaven has prescribed, let it be done with diligence" (Ezra 7:23).
Finally, commit your future -- and your whole life -- to Jesus Christ. By faith ask Him to come into your heart and life, and turn your life over to Him. Then seek His will for your future, because God loves you, and He knows what is best for you.