What should be in the Domain section of the config file in a .net app

I’m trying to implement okta in a blazor app I’m developing and ive downloaded a sample app from Okta to see how it can be incorporated. In the appsettings.json file I have this section

“Auth0”: {
“Domain”: “”,
“ClientId”: “”
}

ClientId seems pretty obvious but what should go into the domain section ?

The sample also states this

“Set the Allowed Callback URLs in the Application Settings to:
http://localhost:3000/callback
Set the Allowed Logout URLs in the Application Settings to:
http://localhost:3000

what should the section be called in appSettings.json for this ?
The sample isnt particularly clear