How much meat should i feed my ferret?

I'm getting a ferret and i want to know how to take care of it before i get it. i read a million things on like no peanut er, citrus fruit and all that stuff and i read that they are carnivores & need meat but none of them told me how much to give them and how often , like a small piece of meat a day like the size of a pinkie nail or anything . i need help !