Hello, CristiM_Ww.

I'll be happy to provide you with more detailed info. Yes, the QuickBooks Desktop 2021 (QBDT) version is still available and supported by Intuit. However, you need to purchase a license key from Intuit or an authorized reseller to use it. 

Once you have the license key, you can activate and start using the software. If you're unsure about buying the QBDT 2021 version, you may download the QBDT 2023 trial version for free from Intuit's website. The trial version allows you to use the software for 30 days, after which you'll need to purchase a license key to continue using it.

Regardless of which version you choose, it's essential to back up your company file. Backing up your data ensures you have a copy of your financial information in case something goes wrong with your computer or the software. To back up your company file in QuickBooks, go to the File menu, select Backup Company, and follow the prompts to create a backup copy.

For additional resources about QuickBooks Desktop users on a Mac, I suggest checking out this article that offers an excellent resource for QuickBooks Desktop users on a Mac who are looking for detailed instructions on how to install and configure QuickBooks on their Mac computers. The article offers a comprehensive step-by-step guide that walks users through the entire setup process, from downloading the software to setting up their company files. Install and set up QuickBooks Desktop for Mac. In addition to the installation instructions, the article also includes valuable information about the minimum system requirements your Mac should meet for optimal performance. This information can help users ensure that their Mac can run the software without any issues. 

Feel free to reach out to us if you have any additional concerns or questions regarding QuickBooks. Our team is always ready and happy to assist you with anything. Take care, and have a great day!