Apple Login
To confirm the Apple Sign In Capabilities, open project in Xcode, select project target and check Apple Sign In Capabilities added or not.
In Apple Developer Account, Follow the below steps to configure the Apple Sign In Capability.
1. Open Keys tab in Apple Developer account, Click on Create new Key button.
2. Enter Key Name.
3. Select Apple Sign In Checkbox and Click on Configure button.
4. Select the App Id in which you want to configure Apple Sign In and Click on Save button.
5. Click on Register button.
6. Click on Done button and read carefully download note for future reference.