Master Drupal Development

<?php

namespace Drupal\my_module\Controller;

use Drupal\Core\Controller\ControllerBase;
use Symfony\Component\HttpFoundation\JsonResponse;

class HelloController extends ControllerBase {

  public function hello(): array {
    return [
      '#markup' => $this->t('Hello from my custom module!'),
    ];
  }

  public function apiEndpoint(): JsonResponse {
    $data = ['status' => 'ok', 'message' => 'Welcome to DrupalZone'];
    return new JsonResponse($data);
  }

}