Bloodborne is much faster. More like DS3 than 1 or 2. There are no useful shields. Rolling and dodging is your main defense. “Spells” are very different. Your L2 is most likely a gun.

Main controls are ALMOST identical; R1 and R2 attack with your right weapon, L1 transforms your weapon. L2 uses whatever is in your left hand. Circle sprints/rolls/dodges/jumps. Square uses your equipped item. Triangle is a dedicated healing button.

The main difference is where Dark Souls punishes brash action, Bloodborne rewards aggression. There is a “rally” mechanic where if you take a non-fatal hit, but quickly attack an enemy, you will replenish a chunk of that lost health.