Configure Logitech G600 mouse on MBP Catalina
This page has a video that shows how to configure devices with G-Hub. It should be very close on the Mac. It's far from intuitive...
https://www.logitechg.com/en-us/innovation/g-hub.html
Edit the Desktop: Default Profile
Click on the Assignments icon on the left sidebar
Drag &amp; Drop the key assignment(s) to each button on the pictured mouse
You can create many different profiles for specific games but the Desktop: Default is the one you want to edit for everyday macOS use.