General Reusability

Hello out there,

I seams that I am not really get the concept how to reuse components.

This is my setup.
I create a Vue component for every page I want to show.

On that page I have the save and the cancel buttton an a custom component that holds my entity for example a contact object.

The Page component loads the object from the backend an passes it to the custom component via, I use emit to return mutations from the custom component to the page object.

I am happy with this so far, but now comes my Problem.
I can’t reuse the components within the custom component because I can’t give back mutations via emit.
Vue complains that props are not mutable.

How is the general Idea behind reusing components.
I Java I would have a page class with my save and cancle buttons, than my my custom class that existsts of multple custom objects.