On Java Edition, you need to start the Java Edition and click on "Multiplayer". Then click on "Add Server" type as Name "SuperSMP" and type in the IP "supersmp.fun". After that, click on "Done" and you can join the server by clicking on it or you click on "Direct Connection" and type in the IP "supersmp.fun" then click "Join Server" and your Done.
On Bedrock Edition, you need to start the Bedrock Edition and click Play then head to Server and Click "Add Server" type as Name "SuperSMP" and in the IP "supersmp.fun" let the port be. After that, click on "Play" or "Save" and now you can join the server by clicking on it and click on "Join Server" and your Done.
On Console you need to Start Minecraft and click Play then head to Friends then Search Friends there you type "JoinSuper" and click Add Friend now you can join the Server when you click join Friend "JoinSuper" and your Done.
On Mobile or Chromebook you need to Start Minecraft and click Play then head Server press "Add Server" type as Name "SuperSMP" and in the IP "supersmp.fun" let the port be. After that, click on "Play" or "Save" and now you can join the server by clicking on it and click on "Join Server" and your Done.