It depends on your interests. If you like superheroes, you might try Marvel's 'The Avengers' series. If fantasy is more your thing, 'The Sandman' could be a great choice.
It is recommended to read novels that are related to your interests. You can find some popular online novels or classic literary works such as Battle Through the Sky, Douluo Continent, Heaven Choosing, etc. These novels had a wide audience and wonderful plots that could help him expand his knowledge and improve his reading experience. At the same time, he could also pay attention to some literary critics and understand their views and works to provide more in-depth thinking and understanding for his reading.
Before reading the Book of Changes, you could read the two books, An Introduction to the Book of Changes and An Interpretation of the Book of Changes, to better understand the basic concepts and terms of the Book of Changes. In addition, he could first understand the background and history of the Book of Changes in order to better understand the ideas and significance within.
It really varies. If you're into humor and satire, 'Deadpool' could be fun. If you like epic fantasy, 'The Lord of the Rings' comic adaptation is worth a look. And for those who like historical fiction, '300' is an option.