Once the Authentication has been successful, you can send requests to the OAuth2 Protected Server using the Public ID Token stored as a cookie.
The OAuth2 Provider Server Component, has several methods to send HTTP Requests: GET, POST, DELETE...
You can pass the Token as a parameter or pass the RequestInfo class if you are using the Indy Server components.
procedure OnCommandGet(AContext: TIdContext; ARequestInfo: TIdHTTPRequestInfo; AResponseInfo: TIdHTTPResponseInfo);
begin
if ARequestInfo.Document = '/private' then
begin
// return OAuth2 profile data
AResponseInfo.ContentText := OAuth2Provider.Get(ARequestInfo, 'https://graph.microsoft.com/v1.0/me');
AResponseInfo.ContentType := 'application/json';
AResponseInfo.ResponseNo := 200;
end
else
AResponseInfo.ResponseNo := 404;
end;