Problem connecting to a Minecraft LAN server
A LAN server is only meant for people on the same network. Port forwarding will not allow a friend to join if it is a LAN server, but a VPN program such as Hamachi will. To play with a buddy on a LAN server, he needs to either be on the same WiFi network as you or you both need to use a VPN. A program called Hamachi is used for this sort of thing all of the time. There are numerous tutorials on the internet for how to use Hamachi with your friends.