Please write a good tutorial for egui !!!!!

Please write a good tutorial that will teach how to use this great library step by step. The creators of GTK have done this (https://gtk-rs.org/gtk4-rs/stable/latest/book/introduction.html). This is why many people choose GTK, because they have a great online book. Your library is amazing and inspiring, but it can be quite difficult to use without good tutorial.
It's amazing that so much effort has been put into creating egui.rs, but there's no tutorial that would organize and teach you how to use and customize the components.
I'm sure that once the textbook is released, the library's popularity will skyrocket.

Start by reviewing egui's existing online documentation and the linked GTK tutorial for the step-by-step structure requested here. Define the tutorial's scope around using and customizing egui components, then confirm that it provides a complete beginner path from introduction through practical usage.

Written by the indexing model from the issue text.