Can anyone please tell me what is the correct way to add sign in with apple?

Thanks for your replay

I used the service ID as client ID from the apple Developer account
and pasted it in
https://mysite.com/admin/third_party_auth/oauth2providerconfig/add

like this

if everything is correct then I believe the problem must be within the apple id authentication file on the open EdX server ( I did not change anything)