Is there a way to redirect a user from our platform already logged-in to the Cal.com platform? i.e. an OAuth or otherwise kind of mechanism. I want to send our users to Cal.com to manage their schedule without making them log in twice.

This is not possible with out hosted Sass option. You would need to self-host and add your own next-auth provider to achieve that.

Okay! We are self-hosting planning on the platform pricing. So we need to implement an oauth system on our platform, then a next-auth oauth provider inside of our cal.com repo.

That would be correct