It depends on your setup I think. If you are just doing the regular phone Bluetooth connection I don't think you have any options other than the predefined messages. IIRC you can edit the predefined messages in setup.
Now, if you have your phone hooked up via USB and you are using Android Auto or Apple Carplay it all changes, in that case it depends on the phone's options because the radio is acting as an extension of the phone. Android Auto supports voice-to-text replies in Android Auto so thats what works for me.
You have to bear in mind, Android Auto and Carplay are not softwares installed on the radio itself. It is software from your phone taking over your car's screen and speakers, so if you need help figuring something out in Android Auto or Carplay the Jeep manual is not the place to look.