If you want to know how modern operating systems work, you should read Modern Operating Systems written by Tanenbaum and Bos. It is a well-written book full of actual information about its topic.
Each chapter of the book deserves to be a separate book. With a few exceptions, all chapters have the same structure: intro with a quick view to chapter's topic, main part, short list of newest researches connected with the chapter. Every chapter ends with a list of exercises and questions to discuss.
It is a book for students. Authors tell us about topics covered by the book enough to understand main ideas, but not so much deep to get bored. No doubt, it could be used as textbook for university course or as a self-study book.
But not only students benefit from this book. IT professionals will find this book interesting and useful. It gives clear explanation how real operating systems work. It shows common things and differences between Linux, Windows, and Android. It's very sad but there aren't chapters about MacOS and iOS.
Of course, it is not a book for operating system developers. But if you are just interested in its topic, it is worth to read.