When we activate the Xiaomi device, we can already set the system's language, but we can change it if necessary without having to reset the Xiaomi smartphone to its factory settings.

Android 10 (MIUI 12.0)
Step 1:  Open the  Settings
Step 2:  Tap on  Additional settings
Step 3:  Tap on  Languages & input
Step 4:  Tap on  Languages
Step 5:  Choose a  language
Step 6:  Tap on  OK
  1. Open the Settings
  2. Tap on Additional settings
  3. Tap on Languages & input
  4. Tap on Languages
  5. Choose a language
  6. Tap on OK

Xiaomi Instructions