I have had the same problem... I wanted to watch a video with a subtitle, unfortunately, you have to copy the video and put the subtitles in yourself... Which isn't that fun. So, in conclusion, there is not really a way to make subtitles appear on youtube :( sorry! I know, it stinks!
How to put subtitles that have picture of a character beside it on YouTube? https://www.youtube.com/watch?v=25fvsOv7XpI just like in this video