@Kardelune
I think you misunderstanding a lot of things, she did not read anything about the book of this world. She was thrown onto another world without her knowing the title nor the setting.
She knew she was in an internet novel world because she's quick witted and the setting are too obvious,
red hair,
blue hair,
blond hair,
white hair guys in a south korea high school ?? like come on?? Thats how she deduced those boys are the male characters and Yeoryong are the 'female lead'. Since she's pretty, smart, kind, and awfully dense when someone likes her. Remember the first time she went to school, Yeoryong greet her to go together and she freak out because she doesn't know this person no matter how many times she said "Im Yeoryong ! Your good friend". She doesn't know anybody nor recognize anyone.
I think this particular world doesn't have a particular book or novel to be based off from her real world either, It is titled
Inso's Law which basically translated to the Law of Internet Novel, it takes all traits from a romantic Internet Novel and meshed it up onto this one particular world. Like the white haired dude is a chaebol (super rich), the blue one is an aloof model, blond hair is super smart, and the red haired is good at fighting. Her new classmates also posessed a protagonist trait from a web novel and she met so many coincidence like that (especially Ruda whom she thought exhibits the usual trope of girls dressed as boys, because she thought sooner or later someone will that background will come)
It is not based on anything that she has read. She's as clueless as everyone. If she knew, she would have monologue-ing about the fate of these boys and the heroine.