Please login your Shopify Admin > Online Store > Pages > Add page > click on Show HTML button then add this code snippet in page:
<!-- RYVIU APP :: FEATURE -->
<!-- / RYVIU APP -->
After that please go to your Reviews page and add review to feature
Please see the details on our demo site https://ryviu-app.myshopify.com/. Got question? Please feel free to contact our Help Desk to get the answer. Thanks.