Thanks ComGrafPL,
step by step.
There are 3 Questions:
1) Is there a setting for this?
If there exist a setting area in Prestashop I couldn' find, please help me to find it.
If there is no setting in the default installation of Prestashop please answer: No.
2) I should change php-code?
I understand you in the way: no need to change.
3) Or any modul?
I understand "Fastest way in module", that where is a module for "Invoice PDF".
Is this correkt?
Which Module you can recommend?
Can you send a link?
::: EDIT 1 ::::
I found this: https://devdocs.prestashop.com/1.7/modules/concepts/pdf/
Yes, its true: "Working on what make a shop an unique experience, as a Developer you will be asked to customize every PDF files that PrestaShop can produce."
But before "customize" I like to send the PDF in the Mail.
First sending, later make beautiful 
Anybody know the URL for a documentation How to put in sending PDF by mail?
I searched in google again. It seems that Prestashop cannot attach PDF to mails by default.
Thats correkt?
yours
Daniel