There are many facets of a productive Ecommerce website and many ways to create one. 

• Stand-alone. This means your entire site is an online shopping portal.
  These are achieved through different shopping platforms. (Some can also integrate with an existing site)
  
  
• Extension. Many web platforms such as WordPress, Joomla, etc have Ecommerce extensions that can be added to a pre-existing website.
  
  
• Subscription Based. For a monthly fee, there are companies offering these services. You input all your inventory, prices, etc. Customer is rerouted to that company's website for the check out procedure.

Without any contact with you, the customer should be able to find answers to all their questions and have a good shopping experience. If not, there should be a form, email, phone or chat window to get in contact with you.

They all have the normal "add to cart" feature as well as using your merchant account to process payments. (credit card, debit card, paypal, etc.

Regardless of which option you choose, there's a lot of work in the beginning to set it up.

You'll need item photos, item inventory, prices, coupons, etc. You need to come up with a process for handling returns, refunds, shipping, etc. that the customer can access.

As the owner, you'll work from your Dashboard to get all the information you need to process orders, input inventory, view best selling items, and lots lots more.

Username: demo
Password: demo

Email: demoen@prestashop.com
Password: prestashop_demo

Username: cubecart
Password: cubecart