How do you make and play custom maps?

I want to make my own maps. I used to do this in the 1990’s with my original version of the game. I found SCM Draft 2 online which I also used in the early 2000s but not recently. Trying to use it, I get an error message saying that the stardat.mpq files cannot be found. Can Blizzard please make a tutorial on how to do this? It’s very sad that the game is not as feature-rich as it was in the 1990s. I am using a new HP desktop with a Windows 11 Pro license, so all things considered I’m not doing anything complex or weird here that would make the process difficult such as using wine on linux or something.