To process an incoming requisition, you'll want to assign the requisition to a buyer.
Step 1: On the requisition detail page, you can assign the requisition to a buyer on the Process Request tab.
Step 2: To assign a user, click into the requisition that you want > Assigned User: Edit > Select User.
The assigned reviewer will be able to process the requisition. They will also receive an email notification about the new assignment.