I transmigrated into the world of a novel that I haven't read

A man who works in an office waiting for a novel to finish so he can read the whole story. However, he was surprised by the information about the ending which made his fans very angry. Many of his fans sent abusive and blasphemous messages to the author. Even so, the man still sent messages of support to the author. After sending a message of support to the author, the man got a message back from the author.



The author

"May I ask you a question? If you had the power to change the ending of the novel, would you want to change it?"



"Hm! He suddenly asked. Change the ending? Of course."



You

"Of course, I would and I would make an amazing ending."



"I see."



After replying to the author's message, the next morning the man was inside the novel the author created. He has to change the ending of the novel in order to return to his world. How can he survive and change the ending when he hasn't even read the novel?