Invoicing is the last thing you will do with an order. Generate an invoice when all actions have been taken on an order. Creating an invoice finalizes an order and you can not take any more actions (besides marking items as returned). If you still have items in an order that have not been shipped when you create an invoice, they will be canceled.

In your Seller Portal account, go to Account Settings and click on Billing Info you can choose to create an invoice Manually or Automatically.

Manual creation lets you customize the information.

Automatic generates an invoice that’s pre-populated with the information from that order