I'm a 63-year-old retired newbie and also have a Yamaha (FG700S). I am making slow progress but I am very impressed with the quality of the Guitartricks lessons. I don't expect I'll ever be a great player but I'm confident I can develop enough skill to strum simple songs and entertain myself while learning to appreciate great guitarists that much more.
Believe in yourself and be patient. You can do it.
Don