enet_init_client(_str("76.215.138.102")...

Thats an Internet IP, so you connect over the Internet? Better use the local network at first, or even, run client and server on the same PC.

When you connect over the internet you must set port forwarding to your server in your router. Better dont start with complicated things before you got it running locally.

I would even start with 3DGS network before you try ANET. 3DGS network is easier to use, you need less commands. Once that works on your LAN then you can connect through Internet or try ANET.