Intuit does a native version of TurboTax Business for Mac, and there is no official "free download" for this specific professional-tier software.
Use software like Parallels Desktop or VMware Fusion to run Windows alongside macOS. Intuit does a native version of TurboTax Business
If you must use a Mac to file business taxes with this software, you can only do so by creating a Windows environment on your computer: Intuit does a native version of TurboTax Business
If you have an Intel-based Mac, you can use the built-in Boot Camp Assistant to install Windows on a separate partition. Intuit does a native version of TurboTax Business
You will need to purchase a Windows license and the Windows version of TurboTax Business. ⚠️ Important 2018 Considerations TurboTax Desktop | Download Tax Software - Intuit