well the component is an individual section that can be used in another component. So like if you have a main page that has a header and footer and navigation bar, then all the different section that you would show are a child to the main page(parent). The sections that are shown on the main page(parent) are siblings to each other.
An easy way to look at that is routing. if the parent is /main, then the children are like /main/children.
Not sure if that's what you're talking about.
If it's just a modal then you can just put it on the landing page.