I think you should choose cms Magento. first of all. it allows you to add a great number of products and categories for them with no limit. Secondly, nowadays it's the most popular platform for ecommerce shops. thirdly, it has a lot of eye-catching themes and designs - be sure your shop would be unique.
There are plenty of ope source content management systems in the market, but I will suggest WordPress or Magento , you can choose any of them to built your next e-commerce project.they are easy , robust and user-friendly