Both Mac and Windows platforms have a feature called "Remote Desktop" which allows a person to control another computer at a distance. This might be used in a work-from-home situation, for example, where a worker "remotes in" to their office computer. Their home computer or laptop basically acts as a screen and keyboard and all the real work is done on the remote office computer. Scammers also use remote access to take over their victims computers. You get a call saying "We are calling from Microsoft and we detected a virus on your computer. If you give us remote access, we will fix it for you" but then the scammers steal your passwords or do other terrible things.
I don't know if Turbotax uses Remote Desktop or if the support feature is something different that is built into the program, but remote desktop might be what you are looking for. I can't point you to specific details of how to use it, but I'm sure those details are available online.
