You can't train a cat. Cats train you.
We have a 15 year old, pre-declawed cat. When she's being a bleeping pest, we either spray her with a water bottle or pick her up and close her in a closet until she's quiet. She thrives on interaction with her people, so closing her in the closet seems to work the best for her pestering.
I would get a cat tower with scratching posts. Have plenty of appropriate scratching options! The more scratching posts, the merrier.