From what I understood when he thought he was in a novel it was part of the dream, so it's possible this is another world and he just had some memories from his past life.
What probably happened is that in his previous life he saw his future in another world through what he mentally described as a novel, and when he reached the "time" of which he saw the future in his previous life, he remembered it while dreaming and confused the two. So he probably died in his previous world and just reincarnated in this world and is now going through what he dreamed about.
It's funny tho because before all this happened the reason he couldn't eat the food in the cafeteria was because it was too greasy or something, so in the dream inconsciously he already knew that he didn't like food that wasn't Mr Kwon's food. And now after he had the dream, and knows Mr. Kwon's food, it just has become a different reason to not like the cafeteria food, nothing he does is actually changing. Because in the dream he had already talked about the profetic dream with the other secretary and he had already not liked the food at the cafeteria. It's just that the reasons for the things to happen have slightly changed. This is very well written, the author is amazing for thinking all of this so deeply that everything matches and makes sense!
Uh i understand now ori think i do... but thank you
am confuse, is he still in a dream or in the book or in real life. bcs i know that he wake up but then what.. smn care to explane me thank