$orderId = 1; // YOUR ORDER ID_x000D_
$items = $block->getOrderItems($orderId);_x000D_
_x000D_
foreach ($items as $item) {_x000D_
$options = $item->getProductOptions(); _x000D_
if (isset($options['options']) && !empty($options['options'])) { _x000D_
foreach ($options['options'] as $option) {_x000D_
echo 'Title: ' . $option['label'] . '<br />';_x000D_
echo 'ID: ' . $option['option_id'] . '<br />';_x000D_
echo 'Type: ' . $option['option_type'] . '<br />';_x000D_
echo 'Value: ' . $option['option_value'] . '<br />' . '<br />';_x000D_
}_x000D_
}_x000D_
}
_x000D_
all things you will use to retrieve value product custom option cart order in Magento 2: https://www.mageplaza.com/how-get-value-product-custom-option-cart-order-magento-2.html