Upgrading to macOS 10.14
I downloaded TurboTax 2020 and tried to open it. However, It said your maOS is 10.13.6. You need 10.14 or later to use this app. My iMac is 27" late 2009. How can I download the latest macOS or at least 10.14 on my computer or can't it be done? Please don't tell me I need to buy a newer iMac!
iMac, macOS 10.13