Sorry for laughing but the question about how often do they bite question did make me laugh. After you are a owner of a snake a while you will understand that each and every one of them hare unique personalities. Every animal is different. That is why a couple of us recommended you get a snake that is a little older then a baby and the current owner knows its personality over a baby that will require more patience and working with in the beginning. I have never been bit by a corn snake but I sure bet some have.
Look at how many personalities of people we have. Then apply that to snakes. Every animal with be a learning curve and trust building for you both.
I have a 7 year old adult female corn snake that was a classroom pet before the teacher retired. If interested and you get the setup worked out PM me and will work out a deal for you. Not looking to rehome her but she would be great for you to learn on. She has to be encouraged to move away with a hook or object before reaching in to get her but once out she is easy to hold. You will learn about tap training with her as well as the experience of owning a great animal. She is not completely easy yet easy enough that you will have a great experience if you do. She will teach you a lot along the way as well. She also eats really well. IMO this is a better animal to learn on than a completely dossal animal that teaches you none thing and then you get another and wonder why you are having issues dealing with them.