Shopify Schema Markup for Testimonials Widget can be rather tough (as it is dependent upon the review applications that you are using), I recommend you leave it to the gurus.  The initial sample code is definitely the summary page; this has a short description of each and every item (movie) https://bookmarkity.com/story19571345/about-prestashop-scroll-to-top-of-page-move-on-a-page-from-bottom-to-top