First, you go to the minehut website and log in. Then you can go to the server dashbored and find your servers (If you have them). The server ip should be there. like example.minehut.gg . You can copy and paste your server ip. When you load minecraft, click on multiplayer and click on "Add server" Then past you ip in the server address. And join the server.
Also, make sure that your server is online.
i hope that i helped...