So I'm working on an application in visual basic that looks like this: But how can I make it actually connect to the server?
You would need to know how a client communicates with a server. Protocol help can be found at wiki.vg. Be warned it's a much bigger undertaking than simply making a spigot plugin. Have fun
Connection to a Minecraft server and then being able to type in commands and have them executed on the server.
Anyways this is a giant application you would need a developer team to for makking this efficant or else you have ALOT of work! Good luck
Well, then I suggest you to use Java since I'm afraid that Java's network API (on the MC server) and VB netowrk API (on the client you'd like to make) use different protocols. Finally, you have to study Minecraft protocols and behave your application like a Minecraft client. Or you can make something simpler: Make a queue of commands on a DB (I think RedisDB is the best for this), make a plugin on the server you want to manage that process all commands in it. With your application, you have just to add a command in the queue on the DB. That's simple, doesn't it? Hope I've been clear.
A giant application? Naahh, a developer team? Nahhh, a lot of work? Yeaa. This can be also done with just 1 person
The network APIs of 2 languages make no difference in the matter. In either case he's going to be either opening up a TCP socket, and sending information over that following the Minecraft protocol, or he's going to make a higher level abstraction and use that. There's nothing magic about Java.
He does not need this but I would suggest it, When I make thing Like this I work in a team, it way more fast then working alone. It's just an opinion.
In my opinion it is better to have a visual editor rather than having to struggle with guessing coordinates when placing stuff.
If that's your opinion, IntelliJ has a really nice WYSIWYG editor for FXML GUIs. Also, at this point, frontend is the least of his worries. You can get the frontend done easily, then struggle with the backend for weeks
You really should try IntelliJ, it does a few things differently, but god damn it is way better than eclipse in every way