After Time Travel, I Discovered That the Male Protagonist Also Has a System?

I am not a full-time author, I just wrote it for my wife to pass the time when she was bored, so you don't need to give me rewards or anything like that. I will not sign a contract for this book, and it should always be free. If you like it, just keep reading. If you don't like it, I won't change the plot or anything. After all, it is just a random work.