When you turn on "Cortana" mode, Cortana will respond when you say the wake word. The wake word can also be toggled with the Win+C keys. Here is how to turn that option on:
- Open Settings in Windows 10
- Go to Cortana
- Click on Talk to Cortana
- In the menu on the right, look for Let Cortana to listen for my voice commands when I press the Windows logo key + C under the section Keyboard shortcut.
- Toggle the button "On"
- When enabled, pressing the Win + C keys will activate Cortana's listening mode.