Prompt login to delete account


When a user would like to delete his account, I force user to enter his credential by using this link

I was following this doc

But it use the NodeJS.

  1. Is there a way to use something else other than NodeJS? I’m using C#
  2. Is it possible to redirect to a page different than the callback URI?
  3. After successfully enter the credential, is there any flag that we could check so we can avoid to ask the 2nd time?

Thank you for your help