Hi Nivin! Welcome to the Disney Parks Moms Panel!
I am very happy to report that yes, you can enter Walt Disney World Resort theme parks to enjoy
Extra Magic Hours the same day as your Disney Resort Hotel Check-in date. A valid theme park admission is required to enter, no matter if you stay all day or just a few hours.
Before we became parents, my husband and I preferred to spend our first 'Disney Day' in a park as soon as we drove into town. We'd arrive in Orlando around 6 p.m., drop our bags off after checking-in, and walk through the gate at 7 p.m. We always planned to visit whichever park offered evening Extra Magic Hours that night. When you think about the math, with a regular closing time of 10 p.m. and Extra Magic Hours lasting until Midnight, that's five hours of fun!
If your tickets were purchased as part of a 'Magic Your Way package', you might have to take a few extra steps more than just showing up at the gate. You will have to check in, either in person or online, to sort of activate your tickets. Depending on the time you arrive, or if you're trying to check-in really early to get to Early Extra Magic Hours, your room might not be ready. But don't fret! After completing the guest registration process you won't have to visit the front desk again. You can leave any bags with Bell Services to be held (or delivered!) for later. And then when your room is ready your Disney Resort Hotel will send a text message of your room number. Your MagicBand will then serve as your room key and you'll be set for a whole vacation fun!
I hope this helped with your travel plans, Nivin, and we'll see you real soon!
~Kristen