Instagram just provides a platform for both, e-commerce websites, brands, and customers. Brands can create a shop on Instagram and show their products to their followers with a special shop link. When a follower visits their shop he or she can view all the products listed there by the brand and choose from them. But to make a purchase you have to visit the official website of the brand. Thus, Instagram does not involve in any payment process. You should ensure the trustworthiness of a brand or website before making any payment and placing an order. You should always choose the COD option if you placing an order for the first time on a website.