This is a truly odd cd, I can't find info about the author or even when this CD was made, The only thing I know is that this CD has a huge amount of Levels for Duke Nukem 3D, Missions for WarCraft II, and Levels for Command & Conquer, Along with Con files, saved games, and various other files (both zipped and unzipped).
This file is not by me and I do not take credit for it either, This file came from Archive.org
To install Duke Nukem 3D maps, Drag them to either the 20th Anniversary World Tour or Megaton Edition's Maps folder in gameroot and place them there or set up a add-on folder in Eduke32, drop them there and run the usermaps option.
Command & Conquer maps require you to place the contents of the zip or rar file into the game's mission folder, WarCraft II requires placing the files into the missions folder and rewritting txt files to add these missions to the game.