A family of Microsoft products that enable users to capture, organize, and reuse notes electronically.
In Office365 OneNote the way it was presented to me there was an option to revert to the "Classic Ribbon".
After reverting I was able to turn off the most annoying autocorrects by following Home/Spelling/AutoCorrect Options.
WARNING: After reverting to the "Classic Ribbon" I can't find anyway to change back to the default.