Help learning to code goes best in the "coding help" section, but here is a quick overview of creating an add-on folder. This will help once you know something about scripting, because the console and non-add-on scripts should be good enough to learn with.
Well, the first thing you need is to make a folder in your add-ons directory with one(or maybe more?) underscore and no spaces in it's name. /add-ons/my_script will work well enough.
After that, you need two text files in there:
- description.txt (You can probably leave it empty, but it must exist otherwise blockland will ignore everything else)
- server.cs or client.cs (This can't be a .txt file, even if file extensions are hidden by your OS.)
If you use server.cs, it will run when you start a server with it enabled. If you use client.cs, it will automatically run when you start Blockland. If you use both, it will run the client.cs when blockland starts, and the server.cs when you start a server with it enabled. If you use neither, then your add-on will not run, so it will only work as a map/music/print add-on (exception: .mis files can still contain code, and will run when the mission is loaded).
Once you have that set up, you have a basic add-on that does nothing ready for you to add to. If you use a .zip file rather than an actual folder, it will work exactly the same, except you cannot directly edit the files inside, at least on some OSs, so it will be more convenient to convert it to a .zip once you are finished, rather than immediately.
One final note: Blockland cannot interact with files added after you start it, so you need to restart if you create a file mid-game. (There are ways around this, but they are rather complicated.) If you edit an existing file, however, you don't need to restart blockland.