Turbo Tax Business is not available to do online or on a Mac. You can buy the Window's version here. And you can have both TT Business and TT Home & Business (or any personal version) installed on your computer at the same time.
https://turbotax.intuit.com/small-business-taxes
Do you have access to a Windows computer?
You can probably run the Windows Business program on a Mac using a Windows Emulator like Parallels. But you would have to buy a copy of Windows to install in it. Google Windows on Mac to get articles on the various options
