In order not to miss any dates or events, we can save them in the calendar app of the Xiaomi smartphone. Of course, we can give them a name, add guests, choose a location, set a repetition, and set the start and end time.
We can choose between the following categories:

Android 10 (MIUI 12.0)
Step 1:  Open the  Calendar app
Step 2:  Tap on  Add
Step 3:  Choose  Event ,  Birthday ,  Anniversary  or  Countdown
Step 4:  Enter a  name
Step 5:  Set a  repetition  or more options
Step 6:  Tap on  Save
  1. Open the Calendar app
  2. Tap on Add
  3. Choose Event, Birthday, Anniversary or Countdown
  4. Enter a name
  5. Set a repetition or more options
  6. Tap on Save

Xiaomi Instructions