In YouTube, the spoken language of a video is fixed at the time the video was produced. But you can read the title, description, and captions, in any language that you want, provided that the creator included the translation for your language.
Note that some YouTube creators will produce some videos in multiple "spoken" languages. You just have to find them.
For example:
Ex-3-12-English https://youtu.be/QW1KA1dg7xQ
Ex-3-12-Español https://youtu.be/SAX09s0aN_0
Ex-3-12-Portuguêse https://youtu.be/6FYbncRsWZ4
To see the Title and Description in your language, you have to set the "Language" in https://www.youtube.com/
Not in your Google account, not in your Computer, not in studio.youtube.com, but on youtube.com itself!
HowTo: https://support.google.com/youtube/answ ... ktop&hl=en
Note that you do not have to change your "Location". It only affects the recommendations.
You can choose the language of the Closed Captions (CC) in the settings of the video that you are watching, using the gear icon at the bottom right of the video, next to the CC icon.