People should avoid Udemy in general, both as teachers and as students. A lot of shady practices akin to MLM/pyramid schemes. The quality of the courses are also terrible and most of the time the content was copied from some website / youtube that you can access free.

Devs I heard of in Japan are only getting into Godot recently, TGS2023 had some talking, we might see more commercial games soon. But nonetheless, you might find knowledgeable tutors there.

Learning Godot will depend on how familiar you are with Game Dev, or Coding anything in general.

If you know nothing about programming and human computer interaction, taking one of those online free courses from universities that merge coding with games might be a suitable starting option. Like this one from Rice you can enrol for free (choose to audit the course) https://www.coursera.org/learn/interactive-python-1 That will give you some basic imperative programming skills, and also learn how coding for games work.

The most important game dev skills you learn are easily transferable between engines, language, etc… So do not worry, it is Python.

If you are experienced with coding, Godot has a bunch of documentation and sample projects you can check.
Either from their repos, or others. My favourite and most recent is Dogwalk from Blender Studios. It is open source and there are some materials explaining what they did. https://store.steampowered.com/app/3775050/DOGWALK/

Find a sample repository of the style you like: infinite runner( flappy birds, canabalt), last-stand/survivor, asteroids, platform, or anything that would be close to the project you have in mind. Find a project and try to understand it. https://godotengine.github.io/godot-demo-projects/ or https://github.com/gdquest-demos/godot-4-new-features have plenty of those.

I remember, back in the day, kids wanting to learn game dev because they wanted to make an open-world survival craft with stealth elements. That is a terrible way to start, find something small or break a big ambitious project in parts and build it from there. For the example I mentioned, first try to learn how to move the player in a small area of your world of choice (platform 3D or 2D).

Once you know what you are lacking, then find a course, video, forum discussion … that will help you with that. I found more valuable information in specialized bulleting boards than any course and YouTube videos combined (but this only kicks in when you are comfortable with the basics).

If you just want to follow courses in general, https://www.gdquest.com/ is your best bet, like the other comment said. They are partners with Godot and are frequently featured in their website https://godotengine.org/article/godot-4-0-sets-sail/. They have plenty of open-source projects and youtube videos (also paid classes). - This is a good start if you like 3D games https://www.youtube.com/watch?v=JlgZtOFMdfc

Let me know if you have anything in mind, I might be able to point you to a better direction.