Are you trying to move your file from QuickBooks 2012 to QuickBooks Online? If so, you will need to restore the file first to a supported version of QuickBooks before migrating to QuickBooks Online.
You can download a trial version from this link: QuickBooks Desktop trial links.
After updating the file on a supported version of QuickBooks, follow the steps from this link to convert your file to QuickBooks Online: Convert QuickBooks Desktop file to QuickBooks Online.
Feel free to reach out to us if you have any other questions. Thanks.