On remembering and retaining the knowledge from the books that I read

I love reading but I have hard time regularly saying no to online distractions in order to focus on a book. I'm also awful at remembering, applying or even explaining the things that I read about. While reading a book I am fully immersed in the story knowing many interesting details about the particular situation, subject matter or person, but only a handful of days later the details get blurry and I have hard time summarizing even the larger points.