Done various jobs in call centres, last working for 111/ambulance service.
My advice? Don’t.
Busy, busy, busy. You’ll be surprised how few people will be taking emergency calls with you. Long shifts. Crap hours/shift patterns. Depressing. Detrimental to your health (physical and mental) crap money. Call after call where people’s lives are in your hands but you’ve not got time for a pee break. Dealing with general public who 99% are stupid. Abuse, not finding out if a patient you’ve helped has lived or not. Sat on the phone listening to the caller vomit/crap. Etc etc.
I left and got a job stacking shelves, that was great!