From your Shopify admin dashboard, click Order.

Click to select the order you want to print PDF files.
Click More Actions -> Print/Preview PDF Invoice by AllFetch.
Then, in the PDF Print page, select to print/download it

From your Shopify admin dashboard, click Order.
Click to select the order you want to print PDF files.
Click More Actions -> Print/Preview PDF Invoice by AllFetch.
Then, in the PDF Print page, select to print/download it