Adding an order one by one may be difficult if you have a few of them, so there is a simpler way by directly importing them.
Once you've exported your orders, open the CSV file that was exported and edit it.
If you edit with MS Excel, make sure that you convert text to columns. Select delimited as "Comma".
Now that you have your columns, add your new order in the format shown in the excel, and do not forget to remove all existing ones:
Once you've done all these, save the file as CSV, click the import button and follow the wizard:
If you have any questions, get in touch at firstname.lastname@example.org