I was very young when I got my first apartment and decided to get a cat from a shelter. I grew up with dogs, had no experience with cats and there wasn't any internet then to research these things. Being young, I just assumed they were removing the claws and had no idea the breadth of what I had done. It was hideous and I cried for a week watching my poor cat, with wrapped paws, hobble around the house. When they removed the bandages, his paws were covered with dried blood. I had to shred up newspaper for litter so not to aggravate the paws and so they wouldn't get infected. Fortunately, it didn't make my cat introverted, but I would NEVER do that again to an animal.
I have had several cats since Oreo passed away, and they have claws. I found that a cheap jute or sea straw carpet was sufficient for them since they never took to the scratching posts. It did not require training. They went right to it naturally. They need something to remove the sheath that grows on their nails and this works perfectly. I also have a big oak tree, amongst many, out front of my house and they come outside and hang with me. They use the tree as a scratching post also. It doesn't seem to damage the tree. Cats will also stretch their claws out when they are happy to knead like they did when they were suckling as kittens. A blanket or their beds work fine for this.