If you have a user account you are able to change your customer profile by yourself. You can create one billing address and multiple shipping addresses. These addresses do not necessarily have to be in the same country. Please observe that shipping fees apply for the country the products are being shipped to.
If you want to add an additional billing address or do not yet have a user account our customer support gladly helps you with changing any of your data: firstname.lastname@example.org, Phone +1 877-302-8632