wahla

Hi, i want to show my whmcs header to my wordpress header or reverse is it possible i mean there must be only one interface to my site currently from my wordpress site using phox theme is redirected to whmcs then comes back i want to use only one header and footer namecrossing.com is my site check by searching a domain and go to purchase you will see redirected to whmcs ..... i don't want two different platforms shown to my customers how is this achieved? thanks in advance