You need to call orderService.completeOrder() on the order, to mark it as complete. You could do this by setting up a subscriber that listens to when an order is paid and shipped, or add a button that makes a request to /admin/order/:id/complete.
#How to change order status 'Processing'?
cerulean osprey
oak dragon
The defination of completed/cancelled is vary. It depends on the payment/shipment method and your own business logic. It is not just a button. I think that is why Medusa team does not add it out of the box
cerulean osprey
Exactly as @oak dragon says we leave it up to the users to specify how they do this. Most often it would be through the use of a subscriber that reacts to the product shipping from your warehouse, etc. So don't think we would be looking to add a button to the default admin, but if you have a flow where you are manually marking products as shipped than it might make sense for you to add such a button yourself, or simply add a subscriber that listens to the order shipped event, and complete an order based on that 🙂