What do I need in order to use a digital product?

You need the right setup for the specific product you bought. That may mean a compatible browser, a modern device, certain software, a 3D printer workflow, an emulator, an image editor, or another technical environment depending on the product. This is exactly why it is important not to buy a digital item based only on the title or the picture. The product type matters. A font, a game, a printable model, and a browser tool do not ask the same thing from the customer. If your setup is unusual or specific, ask before buying instead of assuming universal compatibility.