Incomplete delivered goods

hello everyone, if someone could help me on this subject, for goods delivered but not complete, is it possible to generate a delivery slip

You can create a Delivery Note for the Quantity of items delivered.
Refer to this documentation

thank you for your reply, I’m talking about buying, and when we receive a missing delivery

Can you please elaborate with an example what do you mean by missing delivery?
Do you mean if you ordered 10 qty and received the order in two shipments lets say 5 qty each in both shipments?

You seem to be talking about partial delivery (by the supplier) of items ordered.

ERPNext allows you to enter the quantity received each time the supplier delivers the items. And the PO remains open as long as supplier has not fully delivered the items, unless you manually close the PO.

Hope this helps.