Routing in react if there is more than a page

In react (mainly I mean react/ASP.NET Core) has assumed you have just a page in your application.
But if I have more than one page in my application how should manage to route?
and how to navigate between them.

I don’t know specifically about using with ASP.NET, but I would assume that it is the same. You can use a library like react router to get the effect you want.

Thanks for the answer.
But in react there is a page named app.js.
Can you name the library? can you give me an example if possible?

thanks

The library is named react router.

But in react there is a page named app.js.

No, the file is named that. You think of it as a page because this is a SPA. But with react router, you can define multiple pages and control which one is showing, you can even have the url reflect the hierarchy, the way you are used to in “normal” app navigation and routing. It’s still technically an SPA, but it just has the appearance of a “normal” app.

There are examples in the docs for the library.