GTA 2021 is on scouting.org. They no longer have a section with what has changed so in my quick look:
Para 4.0.0.1 removed the reference to the old Requirements books. Says the first place to check for the current requirements list is the web, not the Handbook or Merit badge Pamphlet. (No need for MBPs or Handbooks any longer)
6.0.0.4
Registration should be done online. BSA ID numbers are not unique to councils anymore. (Good)
7.0.3.0 The Process of Counseling
Acknowledgment that while in person activities are preferred they are not required; (so do all t