Thanks for reaching out to us. I'm here to help provide some insights about converting a Quicken file to QuickBooks Desktop for Mac.
There's isn't a way to convert the Quicken file directly to QuickBooks Desktop for Mac. You'll need to convert your Quicken data into a .csv file first, then import it into QuickBooks Online. Once done, you can now convert the data from QBO to QuickBooks for Mac.
For additional reference, you can check these articles: