Among Bevy contributors (including myself) there is a general hesitance to invest too much time in official learning material that will be obsolete by the next release. Bevy's APIs are beginning to stabilize ... and the appetite (both from users and from Bevy devs) for official material is increasing. The time is coming (soon)!

While you wait, there are a sizeable number of tutorials on YouTube, and we have learning material linked in https://bevyengine.org/assets/#learning as well.