Well, first off I think that you need to take the car to the closest AutoZone where they will read the codes free of charge.
Secondly, I think that it sounds like the alternator has actually crapped out on you!
It is not that hard to change in our cars just a couple of bolts a wiring harness and then the belt.
But to answer your question it is just as simple as unbolting/bolting the terminals from the old battery to the new. But like I said, get a jump then drive to the closest Autozone/Pep boys whatever is closer and have them to test the charging system to tell you if it is the battery or alternator.
Secondly, I think that it sounds like the alternator has actually crapped out on you!
It is not that hard to change in our cars just a couple of bolts a wiring harness and then the belt.
But to answer your question it is just as simple as unbolting/bolting the terminals from the old battery to the new. But like I said, get a jump then drive to the closest Autozone/Pep boys whatever is closer and have them to test the charging system to tell you if it is the battery or alternator.