Configure integration using grant type "Authorization code"

Hi,

I want to understand how to establish the integration between ServiceNow and Qualtrics using the Authorization code grant type. 

I understand we’ll have to perform the below steps:

1. Host an application on the server
2. The user is then redirected to the Qualtrics login page to enter their credentials and grant permissions to your application.

Can someone please explain how to host the application on server and in the second step when user enters the credentials does that mean they need to have a different set of credentials other than client ID and secret to login.