How close is the movie "No Exit" (2022) to the original novel?

Today I got a copy of the novel "No Exit" (2017) with the recommendation that it's a good read, especially with a setting I like. First, I was very happy to start with a new thriller novel, but then I found out, that it's the original story of a movie of the same name; "No Exit" (2022) is the movie adaption of that book and, sadly, a movie I've already seen.

So, my question ist this: How close is the movie to the book? Is it still fun to read the book when you've already seen the movie? [if so, no spoilers pls]

Thx in advance for any helping answer