Amazon pretty much offers their recommendation engine throughAmazon Personalize. Instead, If you want build one from scratch, I strongly recommend you read up the many white papers that have been written on Amazon’s item-to-item recommendation engine. It’s pretty straightforward to implement. Here’s a link to one of them.. What I have seen is that the best performing algorithms are the simple ones that are based on “viewed-also-viewed” or “bought-also-bought”. Unless you are in the research space, stay away from algorithms that claim enhancements through “Deep Learning” or “NLP”. These fancy algorithms seldom lead to any real improvement in recommendation performance.