Bloodborne might be the best one for newcomers in my experience. The base game is the easiest out of all of them (DS2 is, but it’s not the best starting point imo), the rally mechanic is very forgiving and no shields = more satisfying playstyles (hbomberguy has a segment dedicated to this). The upgrade paths for weapons are straightforward unlike DS1, which can get tricky if you want to start infusing or use boss souls. The environmental obstacles are a tad less overwhelming than in DS1 (Sen’s Funhouse, Anor Londo Archers, Tomb of Giants, etc etc)

Overall, DS1 would be better as your second entry, with Bloodborne being your first foray.