You could download some free open sourced sample site, or can even hammer out a simple catalogue and ordering system via code if you’re capable of doing so.
But the thing is that after the customer has paid for their order then comes the REAL WORK, it needs to get the PHYSICAL item to be delivered to the customer and that’s not something the website can actually do!
“How hard can it be to package something up and send it to the post office?” You might ask? The answer to this question is determined by the scale of operation. If it was just a housewife trying to sell some things through a blog, then yes it’s a simple matter of her logging on to check on pending orders, pick all the orders HERSELF, pack all the orders into boxes HERSELF, send it to the post office HERSELF, and then update the order status with tracking number HERSELF. Then yes, it’s not complicated at all since it’s all done by ONE person, and only ONE person needs to know about the state of the order.
Now imagine if it’s an online store of a public company, when an order comes in, the Order Processing department would verify the orders, send it to the Storage Warehouse to pick the items in the order deliver it over to the Delivery department for actual packing and delivery then update the delivery status of the order. All this while that this is happening, the Customer Service department must have enough visibility of the process to be able to answer any customer enquiries that pop up.
Different companies and organizations would have different workflows and auditing requirements than the simplified scenario which I listed above, the most important thing to understand is that the work required to build an Online Store Website ISN’T limited to just making a website which the customer can buy stuff from. Depending on who’s running the online store, the backoffice to support the entire process might turn out to be just as complicated as the online store website itself!