[Vuejs]-How Vue is meant to be used in context of number of pages?

I am guessing you need to read up on Single Page Applications that Vue helps you create.

To drastically change the layout of the page, is equivalent to jumping on a new page. Instead of rendering a new html page Vue helps you to clear the whole page and mount another component while also maintaining the history state for the browser. You can achieve this using routing.

What you are looking for is the official package that handles routing in a VueJS application; Vue-Router.