We can convert the order to an invoice using programmatically from the Order object in Magento.
Prerequisite:
You must have a valid Order Object. To Retrieve the Order Object check the link, Get order data by id programmatically in Magento
Class Magento\Sales\Model\Convert\Order has toInvoice() function that will be useful to convert the order to an invoice in Magento. Continue reading “How to Convert Order to Invoice Programmatically in Magento 2?”