What tools do I use to make this type of plugin?

What tools were used to create this plugin? I'm curious cause I'm trying to add a single chair to drones if possible but lack any knowledge of programs used.

I'm trying to add a single chair to drones
https://umod.org/plugins/ridable-drones

If you want to get started with plugin development, here are some pointers to get started.
  1. Use an IDE like Visual Studio Community (free), JetBrains Rider (paid), or VS Code (with Omnisharp extension)
  2. Install a local Rust server with Oxide, and point the IDE to the dlls in the server's rust/RustDedicated_Data/Managed directory
  3. Use a decompiler such as ILSpy, DnSpy or JustDecompile to view the game source of the above dlls, mainly Assembly-CSharp.dll
  4. Read lots of plugins to see how things are done

thanks plenty WhiteThunder!! will attempt to learn the basics even though you linked me to exactly what I wanted<3 TY!!