Shops and makers
A shop that sells six things does not need a warehouse system. It needs a page that takes money.
Products, and the three kinds of them
Physical products ship. Digital products deliver a file after payment. Subscriptions renew. All three are the same object with a different capability attached, so a shop that sells a mug, a PDF pattern and a monthly box is one catalogue, not three systems.
One cart, two kinds of thing
The cart products go into is the same cart that takes event tickets. Somebody buying a workshop place and the book that goes with it checks out once.
Payment
Checkout is hosted by the provider — Mollie or Stripe — so card details never touch the site. The order moves through its own lifecycle, and what comes back to you is a paid order with its lines, not a notification you have to interpret.
What you write around it
The parts of a shop that sell are the parts a product feed cannot generate: why this glaze, how long the wait is, what happens if it arrives broken. Those are ordinary blocks on an ordinary page, next to the product list.
The other three.
Every one of these is a different job for a website, and most businesses are a mix of two.
Build the version of this that is yours.
Nothing above needs deciding in advance. Turn a module on when the business actually needs it.