Integrating live video chat capabilities in app but user only needs to log into my app once

What is the easiest way to integrate live video chat capability between users on the app and setting it up so that the users do not need to log into any external API and only needs to log into my app once in order to do this?
Thanks

Did you get my reply on your first post about this topic? If so did you not have any luck contacting the user or was it not something that users don’t need to log into any external API?

Yes, the poster never responded. I’m still trying to figure it out.
Thanks