It's not only the screen reader, but the operating systems themselves are fundamentally different in the way they function, from general system navigation to app installation and maintenance. I strongly recommend poking through
$1It really helps, as does the MacOS Help menu found in the Finder Menu bar. If you are used to tab navigation, you can set that up by going to System Preferences > Keyboard > Shortcuts tab and then turning on the Tab key navigation checkbox.
Learn and get used to QuickNav and interaction. I use QuickNav all the time, allowing me to navigate my whole system or websites with just the arrow keys alone without needing to hold down the VO keys. I recommend you check out the Mac VoiceOver group on Facebook; I regularly help folks out there with their questions and needs.
It's never too early to learn how to use Terminal and the command line! I do almost all of my file and folder management through Terminal commands now, but I will admit that can get a little overwhelming trying to learn both that and VoiceOver at the same time. Poke through the options in the menu bars and memorize the keyboard shortcuts! They make overall system interaction super fast and they really help productivity. Here are some good ones to know:
* VO+F8 - VoiceOver Utility
* Shift+Command+H - Opens Home folder in Finder
* Shift+Command+O - Opens Documents folder in Finder
* Command+Option+L - Opens Downloads folder in Finder
* Command+Tab - Cycles through open apps
* Command+Tilde - Cycles through open windows within the currently active app
* Command+Option+Escape - Opens Force Quit dialog to close apps that have stopped for some reason
* VO+ F1 tapped twice - opens application chooser menu that shows system dialogs
* VO+ f2 tapped twiice - opens list of all windows in currently active app
Just a few to start :)