The Block Editor Handbook offers the official documentation, along with some examples, including a Blocks Tutorial. It's improving over time to include more and more information and examples.
The JS for WP site offers some tutorials. The caveat is the Gutenberg Block Development course and the Advanced Gutenberg course were both created in the early days, so the specific code tends to be outdated, but the principles are still similar enough I've found them useful.
You may also wish to search for more specific tutorials once you've run through the basic examples. GitHub is also full of open-sourced blocks. I've personally found it helpful, when searching for tutorials and examples, to make sure I'm using ones that have been written most recently. Anything more than about 6 months old tends to use outdated code - the editor and the way you code for it is constantly evolving.