1. after created shipment, to find out the shipment and PO via ZSD018
2. confirm PO with ZMM008
download format
Fill in PO line and QTY and add A1 and C1 for PO confirmation
3. upload PO confirmation
confirm
4. Go to download Shipment details in ZSD013
5. Post GR+GI with the download file
6. find all the OB and then go to billing via VF01 or VF04