https://learn.microsoft.com/en-us/dotnet/api/microsoft.web.webpages.oauth.oauthwebsecurity.registerfacebookclient?view=aspnet-webpages-3.2
OAuthWebSecurity.RegisterFacebookClient Method (Microsoft.Web.WebPages.OAuth) | Microsoft Learn
Registers a Facebook client with a specified identifier.
methodmicrosoftweboauthlearn