Open the Accessibility Shortcuts panel
Press these keys together: Option (⌥), Command (⌘), and F5. On notebook computers with a Touch Bar, you might need to press the Fn (Function) key as well.
On notebook computers with Touch ID, triple-press Touch ID. (If you press and hold the Command key while doing this, VoiceOver turns on or off.)
To close the panel, click Done or click anywhere outside of the window.
Change the shortcuts in Accessibility Shortcuts
To change the shortcuts that appear in the panel, choose Apple menu > System Preferences, then click Accessibility. Select Shortcut in the sidebar, then use the checkboxes to turn shortcuts on or off.