yes , yes it does
It will depend on the style of karate being taught at your YMCA. They are not the same everywhere. The instructor will be able to provide you the requirements for the various belts.
In normal situations karate is a noun and would be lower case. However, when coupled with a specific style it becomes a proper noun. I study karate. He has a black belt in karate. I study Shido Kan Karate. He has black belt in Shitokan Karate.
No, there is no season for karate. Karate-ka practice all year long.
Not unless it is at the start of a sentence or part of a formal name. Karate is studied in a dojo. He went to the dojo to study karate. He studies Shidokan Karate.
There are tens of thousands of karate students in the US alone.
The same way that any individual trains and learns karate. They study with an instructor.
All ages study Uechi Ryu karate.
Actually some do and some don't. You should try looking at some YMCA sites.
Not if you stay and study it long enough. Eventually all of the skills will be learned. Karate evolved out of kung fu.
Yes, "Karate" should be capitalized as it is a proper noun referring to the Japanese martial art.
where im going is the YMCA, so you should try it