we are trying to figure out a better workflow. we have many sales orders that need to be partially fulfilled. that decsion is made by the front office how can we streamline that the warehouse manger know which sales orders to fulfill but more importantly which items in that order

Have you thought about un-committing the items that management doesn't want to ship and re-committing them when they are released?

Pick pack and ship would require that across all sales we need this only for 1/3 of them

you can create checkbox on item line which will identify which items to fulfill, also you can create a checkbox on sales order which will show whther to fulfill or not

If I create a checkbox on the item fulfillment will the fulfill button that creates item fulfillment only choose the checked one /

you can do this with the help of suitescript. On item fulfillment creation, fulfilled only those with checkbox checked on item line on sales order.

the 2nd wont work