You can fulfill your order 3 different ways:
1) Fulfill the order from a warehouse
2) Reserve the order from a backorder
3) Place a new purchase order if there is no stock
There are clear indications as to the quantity you ordered, the quantity that has been fulfilled and the quantity left to fulfill.
As you choose how you want to fulfill the order (ie you want 1 item from warehouse A), the numbers will immediately update themselves and new quantities will be reflected.
Once you have fully fulfilled your order- you can see there is now a green circle with the words Completely Fulfilled in the summary under All Products- click on the "confirm and fulfill" button at the bottom right hand corner.
If your order is not complete and therefore not ready to be fulfilled, there will be a red circle (with the words Nothing Fulfilled) or an orange circle (with the words Partially Fulfilled) to indicate that
A pick sheet is now sent to the warehouse so that the order can be picked, packed and shipped.
Notice the progress bar at the top- the Fulfillment Status will be green