If you were building this by doing php coding to alter theme files that would be one thing. Adding Elementor to the mix changes it and it is highly dependent on that plugin.
Excluding elementor, I would create a post type for books and a post type for authors and I would have a bidirectional relationship field to connect them. These post types might also have some custom taxonomies. Then I would code the templates to show the information.
Beyond this you should look at documentation for Elementor or seek help from someone familiar with elementor.
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