Traveling Through Another World, I Started My Expedition by Picking up Trash

The story of an ordinary person struggling to survive in a different world full of time travellers. The author writes in the introduction: 1. This book focuses on comparing combat power across works. If there are differences in settings, it depends on my second setting. 2. The author is a novice and his writing skills are not that good. Please forgive me. 3. No heroine. 4. There are some settings and the like that I will complete with the author's words related to the work. 5. Any work settings that everyone wants to see but I don't understand can be posted in the book club, or send a video link for me to watch myself.