There is no official job title or position at Amazon specifically for book reviewers. However, Amazon does allow customers to leave reviews on products, including books, and these reviews can have a significant impact on a book's sales and visibility on the platform.
If you enjoy reading and reviewing books, you can become an Amazon book reviewer by simply purchasing books on Amazon and leaving reviews for them. Many people have built up a following and become known for their book reviews on Amazon, which can lead to opportunities such as receiving advanced reader copies of books from publishers or being approached by authors for reviews.
While being an Amazon book reviewer may not be a paid position, it can be a rewarding hobby for book lovers who enjoy sharing their thoughts on the books they read.