Pick a code editor¶
Before you can write a plugin you need somewhere to write it, and a code editor is the right tool for the job. Two good free choices are Visual Studio Code and Notepad++. VS Code works on any system and colors your code so mistakes are easier to spot, and you can add Lua and YAML support by searching for them in its Extensions tab. Notepad++ is lighter and opens faster, but it's Windows only. Either one is fine, so use whichever you like.
Windows can hide the real file name
Windows often hides file extensions, so a file you named main.lua can quietly end up as main.lua.txt, and then your plugin won't load. To avoid this, turn on File name extensions in the View menu of File Explorer, then check that your files really end in .lua and .yml.
Once you have an editor, you're ready to make your first plugin.