While Pathfix OAuth handles the entire oauth process, you would need to create the 3rd party developer app for the authentication (this allows your app to be the one asking your users for authorization).
We understand that setting up certain apps are more complex than the rest of them. To help with this, the team has documented step-by-step guidelines on how to set your app up with a few of them.
Access the entire list here: Integration Setup Docs - Pathfix | Documentation
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