How to use codeigniter routes on a procedural style PHP website with a codeigniter folder structure?

I have a website built with a folder structure exactly like code igniter which has this folders:

• app (controllers/core/helpers/libraries/models/views/) etc.
• assets
• files
• system (core/database/fonts/helpers/language/libraries)
• themes (default)
• vendor

Codeigniter uses routes via Router.php to map urls so the url looks clean, this means instead of using:

www.example.com/app/controllers/index.php

you just use

www.example.com/

and so on for the other folders, but codeigniter it's object oriented, and this website is made in procedural style.

Is there a way I can reply that routes for my website?

Thanks

There are plenty of PHP routers plugins that you could use, among populars AltoRouter, FastRoute, Klein.php.