Hi and welcome! You've come to the right place.
As for asking advise on how to start your sobriety: You've already started by coming here and by planning ahead of temptation.
See if meetings are right for you, do stay with your parents when you would be out drinking and as for your exams, celebrate by all means, just don't include the drinking/using. Anything but....... Good luck for your exams and staying sober.