Just be excited! And grateful to your parents for giving you this opportunity. Stay real. Spend as little money as you can: you will be very glad to have got into good habits after the first few months.
Don’t fall into any I’m so homesick ruts around the yomim tovim – you’re going to be in E”Y (I’m assuming, or somewhere different and interesting) for goodness sakes! Of course you’ll miss your family but not as much as you might think.
Find someone in the sem to have create a really good relationship with. That’ll take time but you will be so glad to have a mentor, along with your parents, for reality checks through life.
Hatzlacha, and may we all be there sooner than school’s scheduled to start.