I have to figure out how to use OAuth 2 in order to use Deviantart api.
I got the client_id and client_secret part
Here the information they give
Endpoin
In the ASP.NET Core Security Project there is now a ready to use solution:
Nuget Package: AspNet.Security.OAuth.DeviantArt
Easiest thing to do now is get Visual Studio 2013 and create a new ASP.NET Web Application choosing "Individual User Accounts" as your authentication type. There's a working OAuth 2 implementation out of the box in there (configured at App_Start\Startup.Auth.cs) which you can slice out and then adapt to your needs.