Use VoiceOver with the Touch Bar
If your Mac has a Touch Bar, you can use VoiceOver to select and activate items in the Touch Bar by performing gestures directly on the Touch Bar. If you already use VoiceOver on iPhone or iPad, the gestures will be familiar to you.
To turn VoiceOver on or off using the Touch Bar, press and hold the Command key on the keyboard and quickly press Touch ID three times.
Navigate items: Slide a finger or swipe right or left on the Touch Bar. VoiceOver announces and outlines the currently selected item as you move around the Touch Bar. When you slide, VoiceOver also plays sound effects to indicate blank space.
The outline around an item in the Touch Bar is independent of the VoiceOver cursor on the item on the screen.
Select an item: Tap the item once.
Activate a selected item: Double-tap the item.
Select and activate an item: Split-tap—touch and hold the item with one finger, then tap anywhere on the Touch Bar with another finger to activate the item.
For some actions, such as dragging sliders to adjust brightness, volume, or date and time ranges, the double-tap and hold gesture is especially useful. For example, double-tap and hold your finger on an item in the Touch Bar until you hear three rising tones; then without lifting your finger, drag to move the slider.
Tip: When VoiceOver is on, you can enter VoiceOver commands by using the Fn and number keys with the VoiceOver modifier, as an alternative to using the function keys (F1 through F12). For example, to open VoiceOver Utility you can press Control-Option-Fn-8 (instead of Control-Option-F8).