将核心PHP项目文件夹添加到laravel文件夹结构

I have two projects in PHP, one developed in core PHP (say products.com) and one in Laravel 5.5 (say ecommerce.com). Now I want to add the 'products' project folder in laravel project in such a way that the product website will be called by ecommerce.com/products.

In short, how can I add a core PHP project folder in a project having Laravel folder structure such that I can access core PHP project with routing scheme used by Laravel?

Thanks in advance!