Add another SITE in my site

[Celebrimbor]

Hello people.

 

I have a pharmacy online, like an affiliate. http://www.westpills.com

 

When the clients click on checkout button, they are redirected to a billing page: https://mysecurebilling.com, that open on another window or tab.

 

So i want that when the client click on checkout button, the client stay on my site( westpills.com ), like i draw on attached file below.

 

 

There is any way to do this?

 

I want too, that the clients, to access the billing page, must be signin.

 

P.S.: i dont use the payment modules that are usually on oscommerce, because this billing processor dont have support to oscommerce.

 

can someone help me?

 

Thank you

 

Rafael