Hey
Congratulations on your date and super release.
Don't stress out too much, the surgeon who has given you the date should pretty much do everything for you.
They should send out a pack with all the info you need and should send you hospital admission forms or they will inform you how to do it online. You then send those to the hospital direct.
Good luck with it all, but if you have any questions or are unsure, you should definitely call your surgeon.