I'm working with a integration that requires oAuth2 authentication. Has anyone any idea of how this can be done? I have seen multiple examples but they seems to show only how this is done in a Windows application.

My idea is to have a button in the WebApp that says: "Connect to Visma eAccounting" and the user will then be able to log in to their Visma-account, before they will be redirected back to my web application. Somewhere along this function, I need to obtain the authorization code that Visma responds with.