Nurse Liability Questions

I am a recently licensed new grad. I plan to obtain my own professional liability insurance but I wanted to get some opinions fist. Is NSO (nurses service organization) the major provider? They come up first when I google "nurse insurance". Is this the company to go with?? It seems like a really good idea to get some insurance since I might be starting out with some private duty cases at an agency (due to lack of hospital jobs!)

A second question I have re: liability off the job... As an RN, if you witness someone in distress, in need of CPR, are you required to perform it? The reason I ask is 1) I have never performed CPR on a real person and would be terrified if I had to, and 2) someone asked this question in class (pre-licensure) saying that since we are "certified" in CPR are we required to perform it... and the teacher flipped out saying we were NOT certified, all we did was "passed a course in CPR" and that we have no idea what we are doing yet. I'm just confused about what I can and cannot do now (as a bystander) and what I should and should not do. Of course, by nature, I want to help people in emergency situations. I just don't want to compromise my license by acting or neglecting to act.