For more control, such as saving subtitles as separate files, desktop software is the most robust choice.
This tool allows you to download videos and either embed the subtitles directly into the video file or save them as a separate .srt file. how to download youtube video including caption
Tap the Download button located below the video title. For more control, such as saving subtitles as
Widely considered the "gold standard" for advanced users, this free command-line tool can download entire playlists with all available subtitle languages. For more control