Display Total Quantity Ordered

You can add the below

<br/>TOTAL ITEMS: <?= $order->getTotalItemCount()?>
<br/>TOTAL QTY: <?= (int)$order->getTotalQtyOrdered()?>

to the template files under

/vendor/fooman/pdfcustomiser-implementation-m2/src/view/frontend/templates

for example for the order using the default design it would be

/vendor/fooman/pdfcustomiser-implementation-m2/src/view/frontend/templates/pdf/order.phtml

and that would output something like this:

pdf screenshot showing total items and total qty at the bottom

We suggest copying the edited file into your frontend theme to avoid future updates of our extension overwriting this change. Please see here for details:

Theme support / Additional layout customisations