The best thing you could do for yourself is to join a local computer users club.
There's bound to be one in your local area -ask around the local computer repair shops -they should know if there's one in your area.
They will help you learn all these things and more.
Pretty soon you'll be as knowledgeable as the average 3rd grader - Fifth grade is way beyond us older folks level of know how!
(and the way things are these days they know a whole lot more about computers than us older folks)
Good Luck