VDH does not support downloading subtitles. Some videos have subtitles, some don't. If
a video has subtitles, it is sometimes possible to download them with ffmpeg. SOMETIMES.
Not always. But often enough to be worth verifying. If you want to learn how to use
ffmpeg, click this:
https://groups.google.com/g/video-downloadhelper-q-and-a/c/BzPLK2YyL-s
Search for "cannot download" within the text of that web page. That will give you a link
you should click. That will take you to a tutorial on how to use ffmpeg. You need to
read the whole tutorial before you try to use ffmpeg. When I started writing that
tutorial, I believed certain things were important. As time passed & I got more
experience, I realized that the things I thought were important were less so, & I
discovered there were easier ways of doing certain things. So read the whole thing
before you jump in.