Old in age New to GPS

There actually is a book called GPS for Dummies, I even found a downloadable pdf of it, it appears to free to download, please check for yourself

 

It's difficult to explain how to setup and use a GPS because it is tool that can be used in many different ways, so without knowing what you want it to do, the best I can do is to list a few things you might want to do with it.

Even when loaded with maps there is a good chance there will be little or no detail when you get to some out of town area, however you can record where you have been as a Track so that you can always follow it back to a known location I.e. your car

You can mark Waypoints and then 'goto' them by selecting their name such as 'Car'

You can plan a Route before you set out and then follow it, this is best done on a computer running a program such as Garmin Basecamp

There are many other things that can be done with your GPS, if you have something in mind post it here