Play Bloodborne. It's both the most accessible and the best Souls game.
That said, it's also the most skill-based, at least for me. Souls is often a game of trying to complete your build -- or as I like to sometimes say, the difficulty of Souls is everything prior to getting a greatshield. With Bloodborne, you're given a choice of three of the best weapons in the game at the very start and your success is largely based on how well you can parry and dodge.
But the atmosphere is incredible, the lore is enthralling, the music is chilling, the combat is intense, and the bosses (three human bosses in particular, plus another human boss in the DLC) are absolutely exhilerating and cathartic in a way no other other games bosses manages to be, with perhaps the exception of Pontiff Sulyvahn or Abyss Watchers in Dark Souls 3. But those are both basically out-of-place Bloodborne bosses.
