How to limit my puppy’s playtime with the cat

So we have a 5 month old puppy, Misa, and my cat is 3 years old. They love to play together! Which is great bc it’s been helping the cat lose some weight lol. But what I’ve found recently is that Misa just doesn’t know when enough is enough. The cat enjoys playing with her most of the time, and if he’s had enough, obviously he can jump onto the couch or his tree, which she can’t reach. But I want him to be able to relax at times and not always be playing with her/running from her. He’s lived with dogs before, so he’s never hurt her and I can usually go get ready in the other room while they play and not worry about them, and at times he initiates the wild play sessions with her. But she does get too much for him sometimes, like tackling him, just keeps trying to play when clearly they need to take a break- all that puppy energy! Unfortunately, we do have a smaller apartment rn so it is hard to keep them separate, and I need some help looking for alternate solutions. At times, I just grab a toy and put the attention on me and play with her, but as soon as I stop or have to do something, she goes right back to him. I’ve never owned a puppy before (bf has), so please don’t be mean, I’m just looking for advice or command I can teach her to get her to back off, as I don’t want this to continue into worse behavior over time, as she is getting to be the same size/bigger than him now. Thanks for any help!