To ask Siri on your Mac, do any of the following:
Press and hold if available in the row of function keys; otherwise, use the keyboard shortcut as specified in Siri preferences.
Note: Press and hold to ask Siri; press and release to start Dictation.
Click Siri in the menu bar. If it’s not shown, you can add it using Dock & Menu Bar preferences.
Tap Siri in the Touch Bar (if your Mac has a Touch Bar).
Say “Hey Siri” (if enabled in Siri preferences; this option’s only available when supported by your Mac or headphones).
To verify that you can use Hey Siri on your device, see the Apple Support article Devices that support “Hey Siri”.