I'm happy to share with your some insights about restoring a backup file.
The option to restore a backup file is available for QuickBooks Desktop (QBDT). If you want to transfer your file from QBDT to QBO, you can follow these steps:
Open your QBDT file (restore the backup file to your QBDT account).
Go to the File menu, then select Open or Restore Company.
Click on Restore a backup copy, then click Next.
Choose Local Backup and then Next.
Browse your computer for your backup company file. It should look like this: [Your company name].qbb.
Select a folder to decide where to save your restored company file. Then select Open.
When you're ready, select Save. If you see any messages about possibly overwriting your data, select the option that best fits your needs. Don't overwrite anything unless you know you want to.
Go back to the File menu.
Tap on Utilities, then select Copy Company File for QuickBooks Online.
Follow the on-screen instructions to complete the process.