How to Use URL Rewrite to Direct One Category to Another

It looks like you could also solve this using CMS pages. You can always include products in a CMS page too using static blocks or widgets. Have you tried creating 2 CMS pages with the following URL keys?

1. about-vc
2. about-gurkha

If that doesn't help, you can create redirects using the following steps:

1. Navigate to Catalog > Catalog URL Rewrites in admin area
2. Click "Add URL Rewrite"
3. Choose "Custom" from the dropdown
4. Fill out the form with the following details:

Store: The store view this URL rewrite will apply to. You must create one redirect for each store view
ID path: aboutus
Request path: about-vc.html
Target path: catalog/category/view/id/
Redirect: No

This will tell Magento to load a category page when the user requests "about-vc.html". You can change this value to whatever you want.

In order to full fill your requirement, can to use Event/Observer

Create a custom module and using catalog_controller_category_init_after event for redirect to your custom url

see Magento2: redirection from Observer

<?php
namespace [Vendor]\[modulename]\Observer;
use \Magento\Framework\Event\Observer;
use \Magento\Framework\Event\ObserverInterface;

class [YourClass] implements ObserverInterface {
    protected $_responseFactory;
    protected $_url;

    public function __construct(

        \Magento\Framework\App\ResponseFactory $responseFactory,
        \Magento\Framework\UrlInterface $url
    ) {
        $this->_responseFactory = $responseFactory;
        $this->_url = $url;
    }

    public function execute(Observer $observer) {
             $category = $observer->getEvent()->getCategory();
       if($category->getId()=='Match_CatID'){   
         $controllerAction=$observer->getEvent()->getControllerAction() 
             $RedirectUrl= $this->_url->getUrl('chennaievent\index\index');
            $this->_responseFactory->create()->setRedirect($RedirectUrl)->sendResponse();
           exit();
        }
    }
}