1. First, on the mobile phone desktop, find the software "Settings" that comes with the mobile phone, and click "Enter Settings";
2. After entering the setting, slide your finger down to see the setting option of "Acoustic Touch", and click Enter;
3. In the "Touch" setting, you can see that there is a "telephone ringtone" in the middle, click "telephone ringtone";
4. After entering the ringtone, you can set the ringtone according to your own requirements.
References:
Apple official website-Use prompts and ringtones on the iPhone.