Any Geant4 learning materials or tips?

Hello everyone, I am an undergraduate student, currently in my last semester. I am learning geant4 as a part of my research class however I am having really hard time writing my own code. It is like a self study kind of class.
Examples even the basic ones are complicated for me, I can only change basic things in them.

I could not find any tutorials that i can follow. I have checked “Book For Application Developers” in the official website, it is a good intro but not enough.

Does anyone have any material i can follow or tips for learning geant4 in general ?

You may find the Geant4 Tutorials, especially the “Beginnners Course” useful. These tutorials include topical lectures, as well as hands-on exercises.

They are listed on the Geant4 “Past Events” Web page. The next scheduled one (listed at the bottom of the main G4 page) is apparently full.