Thanks, that's very helpful. I didn't know karate had elbows and knees though.
Yeah, that's the problem. You don't know what you don't know. Not your bad; it's perfectly understandable.
Yes, karate has knees and elbows and lots of them. And many other martial arts have facets that are not generally known outside of the students of those arts.
Perhaps the question has been asked and answered, but I did not see it.
What do you want to learn martial arts FOR? In other words, do you seek self-defense training, or sport / tournament martial arts, or good exercise, or what? All are good reasons, but it does help to pick an art sometimes.
What do you LIKE to do? (I saw that asked but not the answer). Do you enjoy rolling on the ground, high kicks, or hard punches? What feels normal and natural to you?
As an example, I am 50 years old and started training at 46. I am relatively short at 5' 10" and I'm heavy. I do not have a lot of flexibility, but I can punch like a freight train and kick like a mule; but I can't kick very high. Oh, I can front snap-kick you in the face, but I can't do the fancy TKD kicks; so my art, Isshin-Ryu karate, is perfect FOR ME. It emphasizes exactly what I'm good at. The question is, what are YOU good at?
In the end, the best art for anyone is the one they will keep training in. If you try it and find you like it, and keep training in it and gain proficiency, then it is the 'best' art FOR YOU.
And really, no one else can tell you what that art might be. We can offer suggestions or tell you what we like about our own arts, but one man's meat is another man's poison. In the end, only you can know what's best for you.
Best of luck, and welcome to MT!