Writers often hover above the books they're reading. We are paying attention to the story itself, of course, but we also have an eye on what the writer is doing and how.
I've heard filmmakers say they do the same thing when they watch a movie: part of them is appreciating the story, but another part of them is paying attention to the mechanics and techniques of the filmmaker: camera angles, light, pacing, textures, etc. We both agree that it can be harder to just kick back and enjoy the movie (or book), but we also learn so much in the process, it's hard to stop!
Next time you read a book, notice when something moves you, surprises you, what draws you in, makes you care about a character or causes you pain. Then take a moment to go back (to the beginning of the paragraph, the page, the chapter) and read the same passages again, watching for what the writer is doing to create that effect. How have they made you feel the way you do?
Is it the unique way they describe something? Does a character come to life through something they say? How much do you learn about characters before you begin to care about them and what did you need to know to become invested in them? How does the writer's voice sound and what makes you able to relate to them? Do they write simply or with flowery language? Notice notice notice and notice.
You may not find answers to all your questions, but if you begin to look for the scaffolding behind the story, you will learn from every great writer you read.