Greetings Jennifer!
Fingers crossed you received your tickets and no longer need this advice, but just in case, I did some research and here are your options.
Hopefully, you have linked the tickets to your My Disney Experience account and have been able to make your FastPass+ selections. If not, you should be able to do so with the confirmation. If you have previously stayed at a Walt Disney World Resort Hotel and received MagicBands, you should still be able to use those (if they aren't more than 2-years old) to get into the parks. If that is not an option, you'll have to
visit one of the Guest Relations locations once you arrive to the Walt Disney World Resort. They should be able to look up the information in your My Disney Experience account, but I would bring along a copy of the confirmation as well.
I'm sure the rest of your magical vacation will go smoothly. If there is anything else we can assist you with, please send us another question.
Pixie Dust,
Lauren