How to Load Order by ID in Magento 2

Magento
$orderId = 1;

$objectManager = \Magento\Framework\App\ObjectManager::getInstance();

$order = $objectManager->create('Magento\Sales\Model\Order')->load($<em>orderId</em>); 

$totall = $order->getGrandTotal();

$shippingAddress = $order->getShippingAddress();

$shippingAddress->getTelephone(); 

$shippingAddress->getPostcode(); 

$items = $order->getAllItems();

foreach($items as $i) { 

 $objectManager->create('Magento\Catalog\Model\Product') ->load($i->getProductId())->getSku();  

 echo "product sku:".$_product."<br/>";

}
-->