1. Create Purchase Order to Principle Supplier - which means that User creates actual purchase order for material to the most used/main supplier. Seek more info about Principle Supplier
2. Create Purchase Order to Supplier - which means that User creates actual order to supplier, but selects supplier manually from the list of suppliers.
3. Add selection to Existing Purchase Order - which means that user adds selected material to the already existing Purchase Order.
ERP - Store
Purchase Order