VAT on custom template

Hi, I have create a custom template wich work fine for invoices.
I would like to display the VAT total amount, but I don’t found the right solution…. (VAT is enable in WC)

I have tried many code snippet but nothing works (I tried to generate invoice PDF on passed orders) :

<?php echo $tax['shipping_tax_amount']; ?>

<?php echo $tax['tax_amount']; ?>

<?php echo $taxes['value']; ?>

<?php echo $total['tax_display_cart']; ?>

Somebody could help me find the right way to display VAT total value ?

Thanks