Hiya Aline!
Welcome to planDisney! I am glad to answer your question as I am a bicoastal Disney Parks fan myself.
The newest generation of Disney Bands or as they are called in the United States, MagicBand+ has the technology in place that will allow it to be
used in both Disneyland Resort and Walt Disney World Resort. You can travel to Disneyland in California and then enjoy tapping into the Parks using the same band back in Walt Disney World in Florida. I'm not sure if you already procured your band but once you have one in your hands make sure to charge it fully. You know when it's good to know when it glows green when tapped. The band has to link to the Disneyland mobile app which may or may not be available for you to download while in Brazil. Once it is downloaded I want you to turn on the band, tap it on your phone (make sure Bluetooth is on), and open up the Disneyland mobile app. Click on the ☰ symbol on the bottom right and then select "MagicBand+." You will see the option "Add MagicBand+" and just follow the prompts to link the band to your account. The tapping to your phone may bring you right away to the correct page but in case it doesn't you now know how to get to where you need to be. If you have tickets linked to your account they should link to your linked band and be ready to use in the Parks. If you continue to have issues look for Cast Members from the Guest Experience Team in the Parks. Use the map feature in the Disneyland Mobile App to identify "Guest Relations" in the Parks to find one nearest to you.
If you wish to use the same band in Walt Disney World in Florida, make sure it appears in your
My Disney Experience Account under "My MagicBands and Cards." In Walt Disney World, the app to download is the My Disney Experience Mobile App. You can make sure everything is linked properly on this app as well. Also, don't think you can only link one band! I have multiple linked to the app as I like to have options. The bands come in such cute designs and I have a few to switch around to match my outfits or mood.
I hope this helps and if you have any questions please feel free to
let us know!
Happy Planning!
-Nimmy