Season 2 of the anime covered untill the epilogue of volume 4 of the novel. If you don't want to wait for the new chapter of the manga or the new season of the anime you can read volume 5 prologue of the novel
Chapter 80 of the manga is volume 4 chapter 18 of the light novel. Although it didn't cover until the end of chapter 18 so if you want to read the novel start at chapter 18 of volume 4
I can share the site where I downloaded the epub/pdf of the novel through private message (bcz idk if it's okay to drop it here)
Season 2 of the anime covered untill the epilogue of volume 4 of the novel. If you don't want to wait for the new chapter of the manga or the new season of the anime you can read volume 5 prologue of the novel
Chapter 80 of the manga is volume 4 chapter 18 of the light novel. Although it didn't cover until the end of chapter 18 so if you want to read the novel start at chapter 18 of volume 4
I can share the site where I downloaded the epub/pdf of the novel through private message (bcz idk if it's okay to drop it here)