I'm sorry you're anxious, and felt the need to post three seperate threads on your situation, but I've been reading this page for years, and don't think I've ever seen anyone actively discuss the call center.
Most of us are grunts at the store level... some at the warehouses.
I've never worked a call center, but my wife has. That doesn't make me any kind of expert, but all those metrics boil down to is speed and accuracy.
Number of calls taken in x amount of time
Number of problems resolved
X amount of time during the call
X amount of time post call
etc etc
You just gotta be fast, and know your stuff. That takes time. Good luck
You'll get trained, and shown how to do everything (I'm assuming). If you get fired in your probationary period, I think it would mean you were really really bad.
Like the person in the other thread said, just do your best and keep a positive attitude. You'll be fine.