Customization in existing Magneto 2 Website

We wanted to do certain set of customization's in exiting Magento 2 Configurable product description issues Product pricing display need to change for variable product Need to display unique short description for variable product Cart page variable product image needs to be unique Alignment of Add & remove button in cart page when out off stock Install ReferalCandy plugin Install Lafitte marketing plugin Need to bring in control such a way that Only purchased customers can put in review. Review in percentage to number(etc: 4.3) Review count and rating in Review page Sort items with Reviews in catalog Optimize searching for better user experience. Invoice customizing: configurable product Type in single line and other minor customization Implement Infinite scroll Help with Refund process in Magento 2 In Report INR symbol not coming properly Full name for product in catalog view