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Check this


 /**
 * @var \Magento\Framework\View\Result\PageFactory
 */
protected $resultPageFactory;

/**
 * @param \Magento\Backend\App\Action\Context $context
 * @param \Magento\Framework\View\Result\PageFactory $resultPageFactory
 */
public function __construct(
    \Magento\Backend\App\Action\Context $context,
    \Magento\Framework\View\Result\PageFactory $resultPageFactory
) {
    parent::__construct($context);
    $this->resultPageFactory = $resultPageFactory;
}

/**
 * @return \Magento\Framework\Controller\ResultInterface
 */
public function execute()
{
    
    /** @var \Magento\Backend\Model\View\Result\Page $resultPage */
    $resultPage = $this->resultPageFactory->create();
    $resultPage->setStatusHeader(403, '1.1', 'Forbidden');
    //$resultPage->addHandle('adminhtml_denied');
    return $resultPage;
}

Check this


 /**
 * @var \Magento\Framework\View\Result\PageFactory
 */
protected $resultPageFactory;

/**
 * @param \Magento\Backend\App\Action\Context $context
 * @param \Magento\Framework\View\Result\PageFactory $resultPageFactory
 */
public function __construct(
    \Magento\Backend\App\Action\Context $context,
    \Magento\Framework\View\Result\PageFactory $resultPageFactory
) {
    parent::__construct($context);
    $this->resultPageFactory = $resultPageFactory;
}

/**
 * Noroute action
 *
 * @return \Magento\Backend\Model\View\Result\Page
 */
public function execute()
{
    /** @var \Magento\Backend\Model\View\Result\Page $resultPage */
    $resultPage = $this->resultPageFactory->create();
    $resultPage->setStatusHeader(404, '1.1', 'Not Found');
    $resultPage->setHeader('Status', '404 File not found');
    $resultPage->addHandle('adminhtml_noroute');
    return $resultPage;
}

Check this


use Magento\Framework\App\Response\Http as ResponseHttp;
    /**
     * @var ResponseHttp
     */
    protected $_response;

        public function __construct(
                  ResponseHttp $response,
                ) {
                    $this->_response = $response;
                }
            public function execute()
            {
              $this->_response->setHttpResponseCode(500);
            $this->_response->setHeader('Content-Type', 'text/plain');
            $this->_response->setBody($exception);
            $this->_response->sendResponse();
            
            }

Check this


 /**
 * @var \Magento\Framework\View\Result\PageFactory
 */
protected $resultPageFactory;

/**
 * @param \Magento\Backend\App\Action\Context $context
 * @param \Magento\Framework\View\Result\PageFactory $resultPageFactory
 */
public function __construct(
    \Magento\Backend\App\Action\Context $context,
    \Magento\Framework\View\Result\PageFactory $resultPageFactory
) {
    parent::__construct($context);
    $this->resultPageFactory = $resultPageFactory;
}

/**
 * @return \Magento\Framework\Controller\ResultInterface
 */
public function execute()
{
    
    /** @var \Magento\Backend\Model\View\Result\Page $resultPage */
    $resultPage = $this->resultPageFactory->create();
    $resultPage->setStatusHeader(403, '1.1', 'Forbidden');
    //$resultPage->addHandle('adminhtml_denied');
    return $resultPage;
}

Check this

    public function __construct(
               \Magento\Framework\App\Response\Http $http
            ) {
                $this->http = $http;
            }
        public function execute()
        {
         $response = [];
         $this->http->getHeaders()->clearHeaders();
         $this->http->setHeader('Content-Type', 'application/json')->setBody($this->jsonEncoder->jsonEncode($response));
        }

Check this 


use Magento\Framework\App\Response\Http as ResponseHttp;
    /**
     * @var ResponseHttp
     */
    protected $_response;

        public function __construct(
                  ResponseHttp $response,
                ) {
                    $this->_response = $response;
                }
            public function execute()
            {
              $this->_response->setHttpResponseCode(500);
            $this->_response->setHeader('Content-Type', 'text/plain');
            $this->_response->setBody($exception);
            $this->_response->sendResponse();
            
            }