Radio favorites are very easy. Since the entire display is a touch screen, a lot of things can be done by touching the thing you want to do something with. For instance, when you start the car, that default screen which shows up has touch access to the most common things. Touch the radio channel part of that screen and it goes right to the radio screen. Touch the faded map area (on the right half), go to maps. You can also swipe left or right to move to other screens.
When on the radio screen, look for a star. Tap that to toggle that channel as a favorite. A solid filled star is a favorite. An outline of a star is not a favorite. You can hop through favorites with on the steering wheel. Left side of the wheel has 2 up/down toggle switches. Left one is volume. Up=louder, down=quiet, press to mute. Right switch moves through radio favorites. Tap up or down to change. It also can scan from the current channel by holding up or down for a moment, until you hear a beep.
People have trouble making sense of a favorite button that operates up/down, when the list of favorites is shown on the screen is left to right. An easy way to remember how it works is to think of your favorite list as a shopping list on paper. First favorite is on the first line. Second favorite is below it on the paper. Third is below that one, and so on. if you are listening to favorite 2, and want to listen to favorite 3, visualize your favorites shopping list. 3 is the next item below 2, so press the steering wheel button down to move to the lower item on the list.
To get home from lost, ahead of time you set up your home address as the favorite destination called "home". Quickest way is to press the voice recognize button on the steering wheel and say (I think) "Navigate Home". Another way is to press the NAV button on the radio and tap the "Home" word along the bottom of the screen.
Once you do these things a few times, they don't take any thinking anymore to do them. There are often a few ways to do the same things (touch screen, steering wheel controls, voice commands) and some might be easier than others for you.
If you really get frustrated, or just want help, there's always the live operator available via pressing the button by the rear view mirror.