Crear una plantilla para Wordpress

We do own a Prestashop site. We need to make Wordpress to be fully integrated on Prestashop, Wordpress installation is up and running, but we have some issues with Prestashop integration. All we need is the blog to be look like our Prestashop site, same header, same footer and we need to show latest blog entries in our Presta site. So, characters type, size and colour (css) should be same as Presta. We need the blog reader to be in our blog and feel as in our Presta platform and viceversa. When a customer places someting in his basket, it is kept when changing to the blog. Blog should be in the same languages as we do have in the Presta site (6 different ones) so, publications could be translated to these languages.