A fulfillment is part of a workflow that begins with a sales order. In order for a fulfillment to be generated, a sales order must be created first. Once the sales order has been created, approved, and inventory has been pulled a fulfillment is generated automatically as part of the workflow.
The fulfillment will start in a status of "Pending Fulfillment". Once the order is shipped either via common carrier (e.g. FedEx, UPS, or USPS) or via another method, the status of the fulfillment changes to a finalized status. Once the fulfillment is finalized, an invoice is automatically generated.