Cannot make out going calls

Hello there, well I am totally new in this Asterisk and Freepbx world.

Just manage to install hand Asterisk + Freepbx and a2billing. I have made two extensions and they are working but I cannot make any outgoing call. I have made a trunk my provider is voxbeam.

I am sure that I am doing something wrong.

Can anyone help me please to complete my setup? Please let me know where to get log or any other details that you guys need to assist me. Please tell me the file direcoty. My OS in Centos 5.7