Custom Module dynamic URL

You can find the same thing in module-cms in this module we are adding text for URL but I think you can easily convert into with small changes. In module-cms you can see that they have created custom router list so you also need to do the same thing. For example,

app/code/yourvendor/yourmodule/etc/frontend/di.xml

In this file, you need to add

YOURVENDOR\YOURMODULE\Controller\Router false 60

Now you need to create your router YOURVENDOR\YOURMODULE\Controller\Router so it can catch every request but you need to make sure that it implements Magento\Framework\App\RouterInterface

     namespace YOURVENDOR\YOURMODULE\Controller;

    class Router implements \Magento\Framework\App\RouterInterface
    {

     /**
     * @var \Magento\Framework\App\ActionFactory
     */
    protected $actionFactory;

    /**
     * Event manager
     *
     * @var \Magento\Framework\Event\ManagerInterface
     */
    protected $_eventManager;

    /**
     * Store manager
     *
     * @var \Magento\Store\Model\StoreManagerInterface
     */
    protected $_storeManager;


    /**
     * Config primary
     *
     * @var \Magento\Framework\App\State
     */
    protected $_appState;

    /**
     * Url
     *
     * @var \Magento\Framework\UrlInterface
     */
    protected $_url;

    /**
     * Response
     *
     * @var \Magento\Framework\App\ResponseInterface
     */
    protected $_response;


  public function __construct(
        \Magento\Framework\App\ActionFactory $actionFactory,
        \Magento\Framework\Event\ManagerInterface $eventManager,
        \Magento\Framework\UrlInterface $url,        
        \Magento\Store\Model\StoreManagerInterface $storeManager,
        \Magento\Framework\App\ResponseInterface $response
    ) {
        $this->actionFactory = $actionFactory;
        $this->_eventManager = $eventManager;
        $this->_url = $url;        
        $this->_storeManager = $storeManager;
        $this->_response = $response;
    }

     public function match(\Magento\Framework\App\RequestInterface $request)
       {
        $identifier = trim($request->getPathInfo(), '/');

        $condition = new \Magento\Framework\DataObject(['identifier' => $identifier, 'continue' => true]);

        $identifier = $condition->getIdentifier();

        if ($condition->getRedirectUrl()) {
            $this->_response->setRedirect($condition->getRedirectUrl());
            $request->setDispatched(true);
            return $this->actionFactory->create('Magento\Framework\App\Action\Redirect');
        }

        if (!$condition->getContinue()) {
            return null;
        }

        // check your custom condition here if its satisfy they go ahed othrwise set return null
        $satisfy=true;
        if (!$satisfy) {
            return null;
        }

        $request->setModuleName('yourmodule')->setControllerName('yourcontroller')->setActionName('youraction')->setParam('custom_id',"test" );
        $request->setAlias(\Magento\Framework\Url::REWRITE_REQUEST_PATH_ALIAS, $identifier);

        return $this->actionFactory->create('Magento\Framework\App\Action\Forward');
        }
    }

In this code, I added 1 flag $satisfy so in this place you can add your custom condition.

If its match then you can see It redirect into your custom controller file.

$request->setModuleName('yourmodule')->setControllerName('yourcontroller')->setActionName('youraction')->setParam('custom_id',"test" );