If you want to have a complete thruhike, your best bet is to do as much backpacking as you can now. Go out in the rain and the snow and the 90 degree days of summer. A lot of people have very unrealistic expectations of the trail. They expect it to be all fun and games, sunshine and butterflies. It isn’t. Especially in the beginning, it is hard. Climbing mountains day after day with a heavy pack in bad weather isn’t always fun. Since you have a year, go out as often as you can. Do a long trip - a week or two. Find out what it is like to be hiking all day every day. Most especially, try it on days of all day rain. You will run into that on the trail. It can be depressing, or it can be fun. Your attitude will determine which it is. But better to find out now, than to wait until Georgia.
Ginny