Issues with VAT and Invoices numbers

Hello,
How to make the mandatory mentions of VAT (on orders and, especially, on invoices) and invoice numbers appear in transactional emails?
I made several tests, no email of invoicing (nor even of confirmation of order) sent mentions the VAT and the number of invoice (it is a legal obligation with which we must put ourselves in conformity as soon as possible!)
The only number that appears is the order number!
Finally, is there any way to attach the invoice in pdf format to the email confirming the shipment?
I’ve created an access to the back office of our site for you to take a closer look – see Site Information
Thank you in advance for your help.
Regards,
Jerome