Connect Local Asterisk to Public Freepbx

Hi

I Have 2 server one is asterisk and other is freepbx. In First Asterisk server i have only enter Private IP address (No internet access) and in second Public Ip Address. One client pc is connect with first one with private sip id. I want that went user dial from First server calls going through second server. can any one help me

You need to ask a specific question. Is this an exercise for school?