Eg: For RL it would be Barto&Sutton book.
Sometimes the best source is not intuitive. Eg: The best way to become a safe driver is to go to performance drivign school - its a bit expensive but they tell you how to sit and stay alert in a car which I have never seen outside of these schools.
One of my most common things nowadays is to ask ChatGPT is to ask to build a curriculum. Creating and understanding what a great curriculum looks like is 20% of the work of understanding a field.
You can LEARN ANYTHING now if you have the time and inclination and elbow grease. Truly nothing is beyond your grasp - NOTHING. Its a magical time.
I'm actually building a tool that will do all this for you and get you started down the learning path faster than what we have now.
And for the curious - the best way to learn medicine is not a textbook. There are solutions out there like Skethcy which work much better for anatomy.
My own learning project - learn Medicine "on the side". It seems ludcirous that we give up the keys to our health to doctors just so we don't have to learn 2 years of courses. Am going to fix that!