help a little!!

I am totally new here,and I was wondering what exactly are these p411 and reference providers?What references are these girls talking about anyway?

Just tell me what a newbie needs to do.

Preferred411 is an escort and client verification service. Its widely used and respected in the hobby to help both parties screen each other.
It is not affiliated with Eccie in any way, but we do work closely with them. You may check them out here
https://www.preferred411.com/index.cfm?fx=Client