PantherExpress Department Buyer training materials are located on SharePoint. The link below will take you to the existing knowledge articles on the purchasing workflow for Department Buyer. This is an in depth training on shopping, managing your shopping carts, checkout, Approval, Purchase Orders, Commitments, Updates, Change Requests, Invoices, NOID resolution and PO Close.
https://pitt.sharepoint.com/sites/purchasepaytravel/pantherexpresssystem/SitePages/Purchasing-Workflow.aspx