Greetings, Wease.

 Allow me to join the conversation and share some insights about the conversion process.

The option to directly convert your Sage 50 directly to QuickBooks Online is currently unavailable. You’ll have to transfer the data to the desktop version first.

Before proceeding, check the computer, and make sure it meets the system requirements. This will help avoid problems when transferring the information.

• Sage 50 and QuickBooks Desktop are installed locally on the same computer.
• QuickBooks database and Sage 50's associated files are saved locally in your computer's hard drive.
• Cross-region conversion is not supported.

When you’re ready, use the tool provided by @Angelyn_T. Once done, you can now transfer the information from the desktop to QBO.

Here’s an article with detailed instructions and a tutorial for the process: Convert QuickBooks Desktop file to QuickBooks Online.

With these steps, the Sage 50 data should now show in QBO.

Let me know about your success transferring the information, or if you have any other concerns.. I’ll be around to help. Have a good one.