How to redirect a puppy away from a cat.

I adopted a 9 week English Cocker Spaniel (working line) and I have 2 cats. One older cat and one 2 year old.

The old one doesn't do anything that the puppy finds fun, and whaps her in the nose (no claws) so the puppy doesn't do anything to her.

But the other cat has no such spark of violence and just runs, which the puppy loves to chase. I'm curious what is the proper way to stop this? Like do I chase after her and pull her away while telling her no? I dont want to just let it happen or the cat will start getting nervous.

Any suggestions on how to squash this is valuable. I really do not want her to chase the cat. I want the cat to be able to safely disengage during any future play.