using back up files

Good afternoon, @annabdrake 

I'm happy to give you some information on the conversion process from QuickBooks Desktop Pro to QuickBooks Desktop for Mac. 

The backup file will not remove the data that's been entered into the Mac version. Once you upload the company file from Pro into Mac, it will create a separate company file that won't be able to be combined with the Mac company file. Here's an article that shows you what data can be imported into QuickBooks Desktop: Import and export data in QuickBooks Desktop

The easiest way to export the data you need would be to export the data into an IIF file. 

Here's how: 

1. Log in as an admin to your company file. 
2. Go to the File menu and click Switch to Single-User Mode.
3. Navigate to the File menu, choose Utilities then Export. Select Export IIF Files.
4. In the Save in drop-down, select the location you want to save the IIF. For example, your Windows desktop.
5. Type a name in the File name field and select Save.
6. Click OK. 

Here's another article that shows you how to import the ILF file into the Mac version: Tasks you can do with IIF files.

Thanks so much for reaching out to the Community. If you have any other questions, please feel free to post again or reply to this thread.