Thank you so much, I think one of the biggest issue in the youtube tutorial is that I'm not using physics_process instead of process for movement. I've added a few pinned comments to fix it, as I'm unable to fix the videos directly. I should probably re-upload the project on itch.io as well. Can you try to see if that makes a difference on your end?
I am very embarrassed and I am very sorry if I caused any stress! As you likely expected, it was a me issue. I believe the issue I had was I was not restarting my browsers when I toggled graphics acceleration. Not a you issue at all! I am a fool!!! So sorry!!!
You do excellent work and you have inspired me to try Godot and build some basic things!! Thank you for entertaining my hopeless self-caused issue!!! I am super happy to be able to play your game on browser in peace now!! :D