How to inject code into garrys mod

Sorry but im a noob at this someone please tell me im confused

Go to C:\Program Files\Steam\steamapps\common\garrysmod\garrysmod\l ua\ And save your code as lua.
To open it type ''lua_openscript NameOfTheLuaFile.lua'' in console

If you can't read the other posts and figure it out all I have to say is that you shouldn't do it.