This section gives you step by step instructions on how to make your mouse left-handed in macOS 12 Monterey, with pictures of the screens to help.
1. Click the Apple icon in the top left corner of the screen and choose System Preferences from the menu.
2. In the System Preferences window, click Mouse.
3. The next step for swapping the mouse buttons depends on the type of mouse you are using:
Apple Magic Mouse: Click the drop-down menu under Secondary click and choose Click on left side.
Non-Apple mouse: Under Primary mouse button, select Right.
4. When you are happy with your settings, close System Preferences by clicking the Close button (red circle) in the top-left corner of the window or using the Cmd + W keyboard shortcut.
Note: If this does not work it could be because your computer settings are managed by someone else (an IT department or administrator for example). If so, you will need to contact them to access these settings or for help.