How to read a book effectively?

I genuinely wanna absorb the book that I am reading like a sponge but I need the foundation of reading and understanding it effectively. What are your ways or principles to understand a book more emphasized or clearer? How to enhance my vocabulary skills? --When I encounter new profound words, sentences, or slangs, I always need to look it up on web dictionary What do you think is the best way of noting, is it writing by hand or typing it digitally by computer, mobile phone, and etc? How do you take notes? Is it by page to page or by chapter to chapter?

Have you ever read a book because it was mentioned here in this subreddit? What book is it, and did you like it?

Discovering new books through online communities can be exciting, as recommendations from fellow readers can lead to hidden literary gems. I'd love to hear about your experience. Please share the title and let me know if it left a lasting impression on you. I'm currently reading The Road by McCarthy. Someone mentioned this book in this subreddit, although I don't remember the specific post. I decided to give it a try, and I was hooked. If you're into post-apocalyptic stories, this book is surely one of the best in the genre.