In order to get started with Deutsche Post International (DPI), we need you to install the app in your shopify store, in order to do that, please visit https://dhlshipping.app/ and enter your shopify URL xxx.myshopify.com. Then you will be forwarded to shopify, to accept the request and install the app.
To do that first manually fulfill your order. View this shopify guide: https://help.shopify.com/en/manual/orders/fulfillment/fulfilling-orders/fulfill-your-own#fulfill-your-own-orders-manually
After that, you can create the DPI label, by opening the orders -> More actions -> Create Label
Then you can select the product that you want to use and hit Create Label button.
After you created all the labels, the final step is to finalise the airwaybill, so head over to apps -> DHL Shipping, and select the airwaybill to finalise for the corresponding location.
Now on the airwaybill page, you see a list of all the labels inside the airwaybill. The next step is to select the AWB copy count and then hit finalise to finish the process.