The tag below your question says that you are using TurboTax Online. If that's true it makes no difference whether you access it from Windows or a Mac.
If you are actually using the desktop TurboTax software installed on your Windows computer, the Windows and Mac software are separate products. If you purchased the desktop software for Windows, call TurboTax customer service during the week and ask them if they will give you a download of the desktop software for Mac at no charge.
