The story is great! It has a lot of potential into it! I think this is going to be awesome in the future! So far, after reading the first few chatpers, I believe this novel is amazign! I commented the things that I think needs editting!
I'd like to note that the events felt a bit sudden. It would be fantastic if you could establish the narration first before placing the system. Let' say that the man was weak, like you've said, author. And in that world/village, violence was always the key. Survival of the fittest. Therefore, he needs to do something. It would be better to explain first the situation he was into. Let the thug beat him up. Show the main protagonist he was not meant to wield a gun, but in the end, he was the "top gunner" in the story. In that way, you can make the story more interesting! feel free to disagree, and these are only my suggestions~ Kudos for the author!