-I started when I was 17. Before then, I only drew stick figures for gag strips solely to tell a joke. I didn't take an actual interest in art until I discovered Yoshiyuki Sadamoto, and then an interest in comics after discovering Jim Lee. My early stuff was heavily, heavily influenced by him.
As for your age, you could be 78 and it'd still be a good time to start drawing. You just have to find the joy in it.
-Almost entirely self-taught. I've failed every art class I've attended simply because I would draw my own things instead of doing the homework.
-If you're completely beginning from scratch, then I would say start with tracing. Trace your favorite characters, the coolest backgrounds, or objects that you find interesting. But just don't do it mindlessly. Pay attention to the form, construction, what your hand is doing as you draw, what your eyes focus on, and all the hidden details that you've never paid attention to before. Get a feel for how long limbs are, how eyes are spaced apart, how wide shoulders can be. Try to ask yourself in what order of things did the artist likely draw their image. Try to get in other people's heads so that you can learn to organize your own mindspace. Drawing will always be scary when you're facing a blank page, so tracing helps you build up some courage, even if it's just a bit.
-My favorite book while I was learning was Perspective for Comic Book Artists.
Main point is to not let yourself get daunted by the difficulty of it all. Strive for challenges and embrace them. If you fail and fall face-first into the ground, you're still further than if you stood still.
Pic is a random drawing from my early years.