How to communicate Cisco IP Phone with freepbx

Hello, I am trying to set up multiple Cisco IP Phones in my office. Their model is spa509g. I was wondering how can I make the phones communicate with the server. Is there an xml packet that it needs? A MAC address? I’m not entirely sure. I do have the freepbx server set up. I have the sip trunk and also my extensions with the outbound and inbound routes configured. I just do not know how to make the two devices connect and configure.
Any help is much appreciated.
Thank you.

If your phomes are using DHCP to boot , then have your DHCP server serve 66 and/or 150 to point to a TFTP server that works. many distributions (Including FreePBX ones) provide just that service, use the “End Point Manager” module to give them something to chew on.

Thank you for that! Sorry about the delay. Also, I have them configured with end point manager and also the DHCP server has option 66 and 150. Is there anything else, because I do not know what else to do when it comes to setting up the phone.