index.php what route do you redirect to?

Hi, I am studying the symfony-demo project and I am faced with a question: This project is configured so that the index redirects to the route / is imagined to be taken out of the locale. The fact is that I want to change the route to which the index redirects when it is set: www.mywebsite.com redirects to the route I want, I do not know how to achieve this, here I leave my index.php:

<?php

use App\Kernel;
use Symfony\Component\Debug\Debug;
use Symfony\Component\Dotenv\Dotenv;
use Symfony\Component\HttpFoundation\Request;

require __DIR__.'/../vendor/autoload.php';

// The check is to ensure we don't use .env in production
if (!isset($_SERVER['APP_ENV'])) {
if (!class_exists(Dotenv::class)) {
    throw new \RuntimeException('APP_ENV environment variable is not defined. You need to define environment variables for configuration or add   "symfony/dotenv" as a Composer dependency to load variables from a .env file.');
}
(new Dotenv())->load(__DIR__.'/../.env');
}

$env = $_SERVER['APP_ENV'] ?? 'dev';
$debug = (bool) ($_SERVER['APP_DEBUG'] ?? ('prod' !== $env));

if ($debug) {
    umask(0000);

    Debug::enable();
}

if ($trustedProxies = $_SERVER['TRUSTED_PROXIES'] ?? false) {
    Request::setTrustedProxies(explode(',', $trustedProxies), Request::HEADER_X_FORWARDED_ALL ^ Request::HEADER_X_FORWARDED_HOST);
}

if ($trustedHosts = $_SERVER['TRUSTED_HOSTS'] ?? false) {
    Request::setTrustedHosts(explode(',', $trustedHosts));
}

$kernel = new Kernel($env, $debug);
$request = Request::createFromGlobals();
$response = $kernel->handle($request);
$response->send();
$kernel->terminate($request, $response);

I would also like to know how the demo redirects to / is as I searched and did not find.