Is the last world about in Kingdom Hearts?

After you see Alice get kidnapped, first you need to go to every upside down room witch you enter through doors in the Lotus Forest. You need to turn on all the lights with fire. After you've turned on every light, go to the main upside down room between the rabbit's hole and the queen's castle. Remember you need to be small. Go on the table and talk to the chesire cat. Then the boss will appear.