Map editor or puzzle by Nival (Blitzkrieg)

Comrades, if you know how to create a full-fledged mission, i.e. set a task (for example, destroy an enemy grouping) and how to insert it into the game so that it can be launched from the menu. Don't be angry, I've been digging on the Internet for a long time, trying to figure it out myself, but I still can't create a mission. I'm making a map, but I can only play in testing mode. I ask you to provide all kinds of help in solving the problem.