1. Taking the Apple 7 mobile phone as an example, you must first open the "Settings" on the mobile phone.

2. After opening, click "Sound and Touch" in the interface option list.

3. After entering the "Sound and Touch" interface, click the switch behind "Key Sound" at the bottom of the interface.

4. If the button is green, it means it is turned on.

5. In this way, the key sound has been successfully set, and there will be sound feedback when the key is pressed.