The answer is similar to somebody who asks you, "How can I have a store?"

It obviously depends on what your specific needs are, such as what type of goods or services you plan to sell, which payment options you want to use, the delivery options, needs for an inventory database, etc. 

The same applies to a store on the Internet. If your objective is to assemble a professional store with many products with links to databases for inventories, etc., you will need to hire professional programmers. 

If on the other hand you have a small number of products and wish a simple solution, you can use the PayPal system to create the payment of each product offered and accepts payments directly from popular credit cards as well as debit.

To use Paypayl with Web Creator, you must register for a Paypal vendor account, and use the tool to create a PayPal button. At the end of the process, PayPal will send HTML code to you. You then copy this code inside a 'Web Object' (Pro version) element and position the element in with descriptions of the product offered on your page. 

You can make as many buttons as you have products. This is a relatively simple solution which usually corresponds to the needs of most SMB's. 

Inserting a shopping cart, integrating the payment system with accounting or inventory requires a more personalized solution. Nevertheless, Paypal offers complete payment solutions, and certain banks also provide e commerce services that can be inserted in your Web Creator web site.