In Shopify, you create shipping labels one order at a time, from the order page. In the Shopify admin, go to Orders and open the order. You can create the shipment in two places:
Option 1: the Delivery Gateway block
Scroll down to the Blocks section of the order page.
In the Delivery Gateway block, check the delivery details.
Click Create shipment.
If you don't see the Delivery Gateway block on the order page, add it to the order details page in the Shopify admin. You only need to do this once.
Option 2: the More actions menu
Click More actions at the top of the order page.
Under Apps, select Create shipment.
After the shipment is created, download and print the label. To see the shipments of an order, click Show shipments in the Delivery Gateway block or in the More actions menu.
You can also print labels for existing shipments on the admin dashboard. See Printing labels.
Can I create labels for many orders at once?
Not yet. Bulk label creation is in testing and will be available soon in the Shopify app and the admin dashboard. Until then, create labels one order at a time.
If you build your own integration, you can already create shipments in bulk through the Merchant API.