On normal? It doesn´t really 'require' anything... find a good group and learn mechanics, be responsive to the environment. Understanding what is going on is more important than whatever DPS number you have.
Of course doing horrific DPS isn´t going to get you very far, but don´t be afraid to try it.
Full disclosure: I have finished pretty much all vet content in the game, sans 12-man trials, with subpar DPS. Find decent people and have fun.
Can purple jewelry drop from normal and I'm assuming its similar or just like vDSA?
From what I read only vet drops purple and Bright-throat jewelry drops from BRP and overland chests. That´s just what I´ve read though.