Magento 2.4: How to change text "Order #" to "Confirmation #" in printed page that appears post order placement?

Question

It happens too often that customers call or email, worried that there were two orders created when they only placed on order. The reason this happens is that Magento issues an order number such as 1001696 when customer places an order on our site– which is presented to the customer on the thank you page. Then they get the confirmation from our order management system called "POMS" with the PO# 112891

Today I made some changes to the thank you page. The page is public_htmle/vendor/magento/module-checkout/view/frontend/templates/success.phtml. Here’s the code snippet with my changes:

<p><?= $block->escapeHtml(__('Your confirmation number is: %1.', sprintf('<a href="%s" class="order-number"><strong>%s</strong></a>', $block->escapeUrl($block->getViewOrderUrl()), $block->getOrderId())), ['a', 'strong']) ?></p>
        <?php  else :?>
            <p><?= $block->escapeHtml(__('Your confirmation # is: <span>%1</span>.', $block->getOrderId()), ['span']) ?></p>
        <?php endif;?>
            <p><?= $block->escapeHtml(__('Within 10 minutes we\'ll send an email to you with your <strong>order number</strong> and complete details.<br />When your order ships we\'ll email tracking information to you.')) ?></p> 

So now it’s possible that more customers will understand that the confirmation number and order number are two different things. There’s one fly in the ointment, however: If the customer elects to print the order number from the thank you page (the link is at the upper right and reads “Print receipt” ) the resulting email begins the confusion all over again. I’ve attached typical email. Note at the upper left corner and again in HUGE letters below that, the confirmation number, named “ORDER #”.

I’d like to get that changed to “CONFIRMATION #”. I’ve tried to find the place where the printed page is created but I’ve run into a dead-end.

Answer 1

This is the title. Check the block

/**
 * @return void
 */
protected function _prepareLayout()
{
    $this->pageConfig->getTitle()->set(__('Order # %1', $this->getOrder()->getRealOrderId()));
    $infoBlock = $this->paymentHelper->getInfoBlock($this->getOrder()->getPayment(), $this->getLayout());
    $this->setChild('payment_info', $infoBlock);
}