Can you train a cat not to scratch furniture?

Hi I don't have a cat but want one when I finally move out of my pet hating household. I was wondering can you train a cat not to scratch your furniture? Because I personally would not declaw a cat because if it ran away then it would not be able to defend itself. So can you buy a scratching post and train it to leave the furniture alone and scratch the post instead? I'm sorry if I sound ignorant but I've only owned a dog and a fish in my entire life so I don't know much about how to raise a cat. I would like to learn how to though as it is important to know quite a bit about how to raise any animal before you go out and adopt one. Does anyone know the answer to this question or have any tips on how to preserve furniture if you own a cat?