A solution to simplify checkout process for customers and staff. -- 2

Hello, I'm Dequan the owner of Avicekeys. Avicekeys is a website digital keys reselling website. I'm looking for a way to simplify the checkout process for our consumers and staff members. Since all of our inventory involve digital keys and licenses, we're needing a way that once a customer makes a purchase for a game, they'll receive an email with that game but also have it stored onto our website. So that they can sign into their account on our website and be able to access their order history and instantly have all the keys and licenses they have purchased. I would need help getting our database to the front-end so users would have easier access. But also allow my staff members who bring in inventory to easily add more keys.