Hi Shin!
There is nothing like a delicious ice-cold beer after a long day day a theme park. Lucky for you, Magic Kingdom now serves alcohol at table service restaurants only. These restaurants take reservations and some book up quickly so you will need to secure reservations ahead of your Magic Kingdom visit. All of the table service restaurants will have at least one beer option but some have a more varied menu than others.
One of my favorite options for a good beer in Magic Kingdom is
Jungle Navigation Co. LTD Skipper Canteen where they have options like Kungaloosh Spiced Excursion Ale and Blue Moon. The food there is also some of the best in Disney World. Make sure to get the Brazilian cheese bread off the secret menu and order the Orinodo Ida's Cachapas as an appetizer. They are the perfect bar food to go along with that beer.
Another great option if you do not want a sit-down meal inside Magic Kingdom is to hop on the monorail and head to one of the 3 Disney World Resort hotels located on the monorail line:
Disney's Polynesian Resort,
Disney's Grand Floridian Resort, and
Disney's Contemporary Resort. Each of these gorgeous resorts also has a full bar where you can just hang out, grab a beer, and enjoy a great view. My favorite bar on the monorail loop is at Disney's Grand Floridian Resort. It is called the Enchanted Rose, is themed after Beauty and the Beast, and is conveniently located on the same level as the monorail exit into the resort. They have several beers there including a pomegranate hefeweizen and a Kona Longboard Island Lager as well as some great snacks and bar bites.
I hope you have a wonderful time at Magic Kingdom!
Happy Planning
Jenna