To join MCC Island, open up the latest version of Minecraft Java edition and head to the 'Multiplayer' tab, then click 'Add Server'.
Input the server IP (play.mccisland.net) in the 'Server Address' box, name the server, so you know where you're headed, make sure you have Server Resource Packs set to 'Prompt' then click done
Voila! MCC Island is now on your server list!
Click on it to connect, and you're on your way to the Island!