If you are allowing employees to requisition items them you might want to remember to publish the catalog otherwise the items won’t show up for the user in the add items option for the requisition. The catalog is the procurement catalog. You will have to do a couple of things before this to make sure the items will display. Set a category on the item. Make sure the categories are published in the procurement catalog. Also make sure the purchasing policy for the user you want to display the catalog is setup to show in the catalog policy rule. If you get all these to align then your released items will show up to be selected in the requisition.
Here is a quick overview.
AX2012 R3 CU11
Cheers
Lachlan