Any good flutter resources for a beginner? (Building in public)

I'm looking for Flutter resources. I started reading Flutter in Action, so far so good.

I see many tutorials, books, videos, but most of them are outdated.

I'm trying to start building quickly. Of course, I'll learn the basics really well first but the goal is to build a production app before January 2022. I don't know if that's realistic or not but I'll give it a try.

I want to consume as much Flutter content as I can, but I want to make sure I'm looking at the best resources in order to save time.

The app that I want to build is a booking app for doctors with different screens for users and doctors.

User will be able to schedule, see appointments, pay, etc

Doctors will be able to manage the appointments, send notifications, etc.

I'm aware apps like this exists but this is my first app/goal for now.

I will try to build in public and share my path with the community.

Any help would be appreciated.

Thanks !!!