I am able to watch this show with my 14y old and they understand swearing at this age so the language used in this show isn't alarming or triggering in anyway, and in some scenes has even been amusing.
After keeping the truth behind Barb's death for a year, Nancy decided to avenge her friend by exposing Hawkins Lab where Barb was finally given a funeral, along with Barb's parents finally getting closure.
I think there is way too much swearing and inappropriate references to sex and nudity.