We can manage the accounts displayed in the Calendar app and enable or disable different accounts for synchronization. By
default, we are shown the phone's account and the Google account selected during initial setup.

Android 10 | EMUI 10.0
Step 1:  Open the  Calendar app
Step 2:  Open the  menu
Step 3:  Tap on  Manage accounts
Step 4:  Enable or disable an  account
  1. Open the Calendar app
  2. Open the menu
  3. Tap on Manage accounts
  4. Enable or disable an account

Huawei Instructions