Standard QBO plans do not offer a single "download backup" button for the entire company file. Instead, you must export data or use specific tools. How do I backup my online data to my computer? - QuickBooks
To download a QuickBooks backup file, the process depends on whether you use or QuickBooks Desktop . In most cases, "downloading" involves exporting your data from the cloud or moving a local backup to a new storage location. 1. Downloading from QuickBooks Online (QBO) how to download a quickbooks backup file