Do you want to translate a YouTube video into your native language? As long as a video is closed captioned, you can auto-translate that video into over 100 languages easily with just the click of a button. You can display subtitles in many languages.
The video must have closed captions set by the original creator (or auto transcriptions by YouTube.) Some videos don't have these, but I'm not sure why.
The quality will be better if the original video creator translated the video professionally, but it still works if the video is auto translated.