What Does It Mean That I Want to Help the Protagonist Make a Fortune from Scratch?

I originally wanted to attend a book launch. As a result, he was transported to another world. I discovered that it was my own book that traveled through time, and I thought I could enjoy it from God's perspective. What does it mean that the protagonist is a slave at the beginning? What do you mean the system doesn't give me anything and requires me to start from scratch? Why do I want to lead a group of passionate young people to overthrow a thousand-year empire? I think it will be difficult for Kassel to regain its independence. But... Despite the hellish difficulty of teammates and the start, this is an era where stars shine. An era of gathering of heroes. A time of rebellion against empire. I am happy to witness this history and to be a person in the book. I wrote this epic poem myself, so I will also accompany the people in the book to witness the fall of the empire.