The call history on the Xiaomi device can be completely deleted, of course, and all entries, such as missed calls or made calls, are deleted and cannot be restored.

Note: You can also delete individual entries by tapping and holding the phone number in the call history and tapping "Clear call history" in the pop-up menu that appears.

Android 10 (MIUI 12.0)
Step 1:  Open the  Phone app
Step 2:  Tap an hold an  entry
Step 3:  Tap on  Select
Step 4:  Tap on  Select all
Step 5:  Tap on  Delete
  1. Open the Phone app
  2. Tap an hold an entry
  3. Tap on Select
  4. Tap on Select all
  5. Tap on Delete

Xiaomi Instructions