Where does the game sit compared to the book?

I only learned about the video game once I was maybe 80% through the book and I've now since finished the book.

I just had a look at the trailers and I'm struggling to see where it fit within the book. The trailer seems to include a bunch of alien races I don't know about. Is this some kind of extended universe or did I read the book too quick and missed a bunch of things?

I saw another thread mentioned a TTRPG which I also had no idea existed so maybe there are more stuff in there? would you recommend I check it out before the game comes out?

Do we know how far in the past/future the game takes place compared to the book?