Even though Drupal was not original built for supporting great eCommerce systems such as other open source framework like Magento, it has lot of modules to set up an online stores. We can set up products, which are a special content type with a field for the price, category, stock, colour, size.
There is a module that implement the baskets and other modules that support different payment gateways such as PayPal, Barclays card and all different card association such as Visa/MasterCard/American Express.
How to set up a Bootstrap sub-theme in Drupal 8
Create your own Theme from hundreds of existing themes and then customise it. This is a fantastic feature in Drupal to implement any kind of design in terms of look, feel and structure. Set up your regions such as the 12 grids responsive layout, Omega theme, very good for mobile.