Yes, you can buy products on Shopify. You can either buy them through the Shopify platform itself, or through a third-party provider.
If you want to buy products through Shopify, you will need to create a Shopify account and then add your credit card information. Once you have done that, you can browse the Shopify store and add items to your cart. When you are ready to checkout, you will be asked to enter your shipping information and then you will be able to review your order and complete the purchase.
If you want to buy products through a third-party provider, you will need to find a provider that supports Shopify. Once you have found a provider, you will need to create an account with them and then add your credit card information.
After that, you will be able to browse their store and add items to your cart.