Under Sales you see all incoming orders and can open each line in detail.

1. Open the order and prepare the goods.
2. Choose the shipping method for the matching zone.
3. Set the status to shipped, the customer is notified automatically.

You only see your own orders. Full details in the documentation: Orders and Fulfillment.

Once an order is paid and waiting to be shipped, you will see a notification in the bell icon at the top right; clicking it takes you straight to your sales.