What is Touch Bar? It was installed from MacBook Pro (Late 2016) Even when the app is running, you can always operate the buttons from the Touch Bar.
Customizing the Control Strip
Volume Slider Mission Control Spotlight Play/Pause Volume Slider Mute Siri Notification Center Do Not Disturb Screenshot Audio Input Input Source Dashboard Launchpad Desktop Display Screen Saver Lock Screen Sleep
Brightness slider (display brightness) Volume slider Mute Siri
customization
Remove button from Touch Bar When you drag and drop a button from the Touch Bar to the display
Add buttons to the Touch Bar Drag and drop buttons from your display to the Touch Bar
See here for how to use and set up the Touch Bar/Touch ID.
How to use and set up Touch Bar/Touch ID