When an Order is created on Spoonfed, it must be given a "Payment Method" or Type.
There are 3 Payment Methods - Account, Other and Card
Account and Other - both require the Order to be separately invoiced in the Invoice Module.
See further article on Invoicing, here.
With Payment Method Card, there is no separate invoicing process as the Customer is emailed a receipt on payment of the Order. See further article on Payment, here.