There’s a lot of good material regarding WW1 in the FAQ here. I think the “Lead up and causes” section would be most helpful to you.
There are two particularly good responses in that section here, and here. The first post by u/kieslowskifan discusses what Austrian Emperor Frank Joseph thought about WW1 after it ended, and the second by u/BeondtheGrave details some of the main causes of WW1.
Hopefully these will help you understand why Germany shares a lot of the blame, I’m sorry I’m not skilled enough to answer directly.