Yes, you can use cloud drives to save your QuickBooks for Mac 2019 data, snyd2706.
Aside from the iCloud drive, you can also use DropBox, Box, and Google Drives.
Before using iCloud sharing with QuickBooks for Mac, you might need to know about the do's and don'ts. You can check the details in the article you've mentioned earlier: ICloud Document Sharing and QuickBooks Desktop for Mac 2019.
Feel free to get back to us if you have more questions about this.