Consume Workday REST API with oAuth 2.0 in .NET MVC

I am trying to call the Workday REST API in my .NET MVC application and am having trouble with the oAuth 2.0 aspect of it. Although in my case I am talking about Workday in particular, I think what I am not understanding can apply to any oAuth 2.0 enabled API. I am trying to use the Authorization Code Grant type.

My understanding of the flow for oAuth 2 is as follows:

1) I send a GET request to an authorize endpoint

2) The user has to log in using their credentials

3) At this point, a response is sent from the API with the Authorization Code Grant in the reponse

4) Now I can make a POST workday xxx request to exchange the Authorization Code for an Access Token

5) I response is sent back with an Access Token

6) Now I can freely use that Access Token to make GET requests