Be aware that if you land on an American tutorial, it MIGHT show you a different way to knit. I know that, here in Germany, they knit completely differently, as they do in France.
A friend of mine was knitting in a doctor's waiting room (in Germany) and a lady commented on what a funny way she was holding the needles. It put her off knitting for good!
Having said that, I'm not sure if the American way is different. In the end, it's the result that counts, and if you're not going to be doing it in public, then it doesn't matter how you achieve the result. I just thought I'd mention it because American tutorials will come up if you search in English.
My problem is that my knitting is very uneven - this is because I was never able to loop the wool over without taking my hands off the needles, I think. And as this is even more divergent from the German way, I gave up, too. I stick to crochet.
In fact, if your hands and arms are weakening, or in pain, due to your health problem, crochet is an interesting alternative, as you do not have to bear the weight of the article you are working on.