Just passive book reading can be boring. You can add a bookmark in your book that helps you to retain the information you have read.
Daily notes review helps you retain and solidify the information in your memory. It helps you to enhance your understanding of the topic.
Random book reading is sometimes boring. You can pick a book that intrigues your interest and helps you to remember your key findings in a book.
Whatever you read, you can try to make a summary. It will help you get an overview of the topic. Plus, it helps you retain the information without skipping the main events in the book.
You can figure out if a book is worth reading or not. More books will not help you to retain your topic. Try to pick books with key ideas of your interest.
You can highlight passages that resonate with you or seem important to you. You can highlight the lines or quotes from the books with a colourful pen so that you can retain those lines in the book.