When your supplier confirms the goods have gone, record it. That closes the line and lets you invoice the customer.
Mark it shipped
Open the sales order and click the Dropshipment tab.
Click New dropshipment.
Enter the quantity your supplier sent.
Save.
There is no commit, pick or pack. Those stages exist because someone in your warehouse has to find the goods and box them — on a drop-ship line nobody does, so the shipment goes straight to shipped.
Partial is fine
If your supplier sent part of it, enter what actually went. The rest stays outstanding and you record it when they send the remainder.
Your stock does not change
Nothing moves in your inventory, because nothing of yours was involved. The only numbers that change are on the order — Shipped goes up, Remaining goes down.
That is worth knowing if you go looking for a stock movement afterwards and cannot find one.
Wait for the supplier to confirm
Only mark it shipped once your supplier says it has gone. Marking it early tells your customer their order is on the way and lets you invoice for goods still sitting in a warehouse you do not control.
How to know it worked
The line on the Dropshipment tab shows the quantity under Shipped and Remaining goes to
Once everything on the order has gone — drop-ship lines and your own — the order turns
Fulfilled.