Head to https://www.shopify.com/, one of the most popular E-Commerce Store Platforms in the world. Can you play with the platform and learn how to add products, setup inventory and prices, pick a store theme and launch?
Shopify offers a demo payment gateway too to test your store from browsing the catalog -> adding into cart -> providing payment details -> checking out and -> creating an order. You get a 7 or 14 day free trial on Shopify to explore the system. Make the best use of it!
https://webflow.com/ecommerce is another option worth checking out.
NOTE
What you learned is just a quick and super fast mode to launch an e-commerce store. However, running a commercially viable E-Commerce store is a professional skill. You need to learn/understand how to do Digital Marketing, how to do Customer Service, how to work with Logistics Partners, how to launch and manage promos/offers and sales events and a lot more. Udemy has some good courses on these subjects if you are interested.
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