I watch Boruto without subtitles these days. I don't understand absolutely everything, but I do understand just enough to get a decent general sense of what's going on. I'd say at least that is what you need.
I wouldn't recommend pausing a TV show or movie or what have you to look up vocabulary. Or stopping reading a book or manga to look up vocabulary, or anything else. That just takes you out of the experience and stops you from enjoying the story. If you can't understand enough to enjoy the story without doing that, I'd suggest just choosing an easier show/movie/book/manga/etc.
You also shouldn't use watching TV as a primary means of learning a language in my opinion. You can learn bits and pieces here and there, but actual practice talking to real people is much more helpful for learning than watching a bunch of fictional people talking to each other.