hmm. I think that Lemon Jelly was the first band to really open the doors of finding my own music, so maybe them because it would technically lead to all the music I ever find.
Other than that, not the band but the song When You Sleep by My Bloody Valentine
was an absolute game changer for me (it was and still is my favorite song ever), and the intense feeling of like, this is the best thing ever holy moley
i felt after hearing it for the first has never been matched by any other song I've heard. So that song specifically.