1) As long as your MBs are listed in
MDE and show as Active, you’re good to go. They’re automatically linked to any and all information in your MDE account - resort reservations, tickets, ADRs,
Genie+, etc. If they’re marked Inactive, tap to reactivate them.
2) In the MDE app, tap the 3 lines in the lower right corner to open, well, I don’t know what to call that page! Anyway, tap on Disney MagicMobile and follow the instructions there. There are videos online, if needed.
3) You can get a key card at the front desk of your resort, if staying onsite, that will function just like a MB. You can also or instead get a ticket card at the tapstile the first time you enter a park. Just ask the CM.
Have fun!