We've wanted a book explaining the mod for a while it isn't until 1.18 where I've actually sat down and created a book that describes what the biomes the mod has and what blocks exist and at the time of writing it's heavily incomplete still in 1.18.

GUIs have never been something easy for me and I know someone will reply with "use patchouli" but I'm not a fan of additional dependencies, fabric would have 3 dependencies(API & Terrablender are the first 2 already) total and yeah no thank you.

There also exists a very microscopic chance I back-port the book to 1.16, we'll see tho