Welcome to QuickBooks Community space, Tina. Let me help you regarding with exporting QuickBooks data to TurboTax.
Note that QuickBooks Desktop allows direct import into TurboTax. You can import your QuickBooks Online account into QuickBooks Desktop (QBDT) and transfer the data to your TurboTax Business Desktop account.
You can have the free trial version of QBDT if you don't have a QuickBooks Desktop account to access the latest version and edition.
To import, you can see his link for detailed steps and explanations on importing the data into TurboTax: How do I import QuickBooks data into TurboTax Business?
On the other hand, to prepare your client's QBO accounts for tax season in the future, use Prep for taxes. This article provides a guide on handling the accounts: Use Prep for taxes to map and export your clients’ tax info.
Count me in if you need additional help with importing QuickBooks to TurboTax. I'm always ready to assist. Take care and have a great day.