Hi, I'm Robert and I'll be helping you with your computer question.
My cats walk on my keyboard all the time. They can be royal pests.
But as much damage as they can do to a document i am typing or the website i am on or even some of the computer display options.
It is not possible for them to render the computer unbootable where nothing happens when you push the power button.
that is a physical problem and it would require repair. It might be a bad mother board it might be as simple as a wire broke somewhere in the power supply. There is no real way to know without having an expert actually look at it and take it apart.