I've had a funny experience as a newbie so far
Early on I wandered off to Old Yharnam before dying 50 times (not exaggerating) to BSB. About the 5th or 6th attempt my summon hunter did very well surviving his 3rd phase while I got hits in here and there. BSB was literally one hit away when summon died. I threw molotov. Freaking BSB jumped at me, dodging the cocktail mid-air, and killed me on landing.
I ran out of cocktails and insights so started taking him melee seriously. Ended up draining my antidote supply. Accidentally discovered that he could be parried, and drained QS bullets from parry attempts. Eventually used up all blood vials as well.
So I got really good at reading his moves throughout. Consistently getting to phase 3 without using any consumables (didn't have any tbh) but always died from one mis step or poison. Then my dumb brain cell realized if you dodged right into his combo he's useless for the next few seconds.
About halfway through the game rn after beating the spider boss. I have died less than 3 times since BSB. Should've fought the Vicar and explored around before BSB in hindsight, but alas.