How to pass component state to child vue?

Question

JavaScript

Hello! I'm doing a serious project on vue for the first time, so forgive me if the question is extremely stupid. There is such a component structure
TheHeader.vue --> HeaderLogOrReg.vue - here you need to catch a click and pass a boolean value to another component that is in such a structure.
App -> Modal - in the modal, you need to accept the state with HeaderLogOrReg

Answer 1

https://codepen.io/nvdfxx/pen/qwRbOY?editors=1111
In general, if

I'm doing a big project

, then it’s somehow strange not to know the basic things, and for a serious project, the event bus or store is usually used like, you will most likely open the modal from not only one component

Answer 2

https://ru.vuejs.org/v2/guide/components-props.html