There's a huge difference between creating a store inside a website and creating an e-commerce website. The main difference is that the first option is a website with a small store in it, the second consist of an entire store made mainly to sell. How can we know which one is the best for me?
The first thing to consider is if the company already has a website. In that case, it may be considerably cheaper to integrate a store inside the website. The second factor to consider is the expected amount of sells. The bigger it is, the most advisable to have a separate e-commerce platform.
To sum up, If you expect a large number of sales, we will advise you to get an e-commerce platform. If not, it will be cheaper and easier to integrate a small store inside website wether if you have it or not.