Cannot find Chinese or Japanese in Character tool box

James is 100% correct here. That being said, there are ways to add languages to that list in your plain vanilla North American install of ID - I have instructions & files to do so via opening edited IDMLs, I recall. (Maybe it was actually opening INX files? It's been too long, I don't recall the specifics.)

However: doing so with Chinese or Korean or Japanese would only let you mark text with that language. It wouldn't actually give you any of the things I'd imagine you want if you were to mark text as Japanese. (Like vertical RTL layout, dictionaries, mojikumi, kinsoku, etc.) You basically can't do any of those things without a CJK install of InDesign, unless you're using scripts or templates to turn the J Composer on, and even then you have very little control over your CJK layout. 

I do it all the time, though. I do a fair bit of Chinese layout, but I have to fake it. If I'm using the World-Ready Composer (instead of the J Composer), then InDesign will happily start a line with a fullstop character, or a Chinese close parenthesis, which wouldn't happen if I were using a CJK install of InDesign as I ought. So I do a lot of manual layout when working in Chinese; lots of No Break applied via Find/Change or via GREP Style, in order to prevent incorrect line endings and such. 

I don't do much Japanese, and if I did, I'd have to have both a CJK and a Middle East install of InDesign at hand to lay out all those languages correctly. 

So: the answer to your question is: "Yes, but I don't have a solution at hand for you, because it's not useful to just add the langtag and nothing else. If you have a compelling reason to add language names to that list without any of the necessary support for working with those writing systems, I could go digging around in my offline backups for the hacky duck-tape workarounds posted a decade ago."