Use VoiceOver and the Tab key to navigate on Mac
In Keyboard System Settings, you can set an option to use keyboard navigation to move the keyboard focus between controls such as text boxes, lists, radio buttons or tickboxes. When you turn on the option, you can press the Tab key to move the keyboard focus forwards, or press the Shift and Tab keys at the same time to move the keyboard focus backwards.
See Use your keyboard like a mouse.
When you turn VoiceOver on, the keyboard navigation option is automatically selected (if not already on). When you turn VoiceOver off, it’s deselected (if it hadn’t already been on). To turn the option on or off at any time, press Control-F7.
When you use the Tab key to navigate while VoiceOver is on, keep these points in mind:
To navigate in reverse, press Shift-Tab.
When the VoiceOver cursor lands on an item, you immediately interact with the item (you don’t need to enter a command). To turn off this automatic interaction of the Tab key, open VoiceOver Utility (press VO-F8 when VoiceOver is on), navigate to the Navigation category, then deselect “Automatically interact when using tab key”.
Note: VO represents the VoiceOver modifier. See Use the VoiceOver modifier.