How-To set information pop-up on terms of revocation purchase

[BarryPresta]

Please help me....

 

I uses the search button but i can't find the answer to my question. I'm from Holland so please excuse my bad English.

 

The problem is;

 

In my PrestaShop i sell online downloadable products (files). The law in the EU tells sellers of these products that the customer agrees with the terms of revocation by proceeding the purchase of the item (before check-out).

 

Is this possible in PrestaShop? And if so, can you please tell me how to add such a pop-up before purchase?

This  is a example of what i want in my shop: