I so recommend you give it another shake. Everyone said it, but until like 2 years ago I didn't understand what everyone was saying. It truly is a rhythm game. Even the big gate keeper genechiro (? Dunno how to spell it) really only boils down to like 5-6 easily recognizable patterns. It took me 3 days of hours after work grinding, with YouTube's help. But I'm kinda into the banging of head against brick wall until it cracks.
But once it clicked, it really clicked.
After you beat him, you get a memory you can use to re fight him. I didn't even use one gourd. After that the game became so much easier!
The "parry" window is so much more forgiving than you're used to, you just got tap it kinda quick. Shit, you could probably spam it fast enough for most fights. But it's such a beautiful game!
Like I know all souls games are pretty in a dark way, but sekiro hits different with the actual foliage, wilting cherry blossom trees, non human skeleton like mountain sides. I beg everyone to try your best to get through at least to that boss, cause he really is a teacher more than a roadblock. You've surmounted seemingly impossible challenges before and came out victorious. You can do it again, it's so rewarding!