Hello. After A Fall, And Hitting My Head, I Had

Hello. After a fall, and hitting my head, I had a CT scan. The Scan showed I have a SubArachnoid cyst. I have an MRI scheduled, but I am very nervous. Recently a family friend found out they had a cyst on his brain which required surgery. Do all cysts on the brain require surgery, and if so, how serious is the surgery and how is the surgery performed? Thank you, in advance, for your assistance with ths.