First step for you to make would be to learn some really basic principles of modding. Basically, learn what scenes are and look into module_scenes.py to see the file's contents. You will see simple tuples of code which constitute a vital part of any scene.
Second step would be to check if your target module has its own source released for everyone. See this thread:
https://forums.taleworlds.com/index.php?threads/guild-of-craftsmen.116434/. Diplomacy's code has been out since 2010, but people made many variations of it which might not be open-source. You have to check yourself if it applies to 4.litdum as well.
Third step would be to follow the instructions contained in the pack's directory. Essentially, you will have to copy the .sco files and paste them into <your mod>/SceneObj. Also you will have to copy the scene entries and paste them to module_scenes.py. Everything is explained in the instructions.
Good luck. It is really easy to understand once you have grasped basic principles of modding. You have to do it on your own, but you will succeed if you follow the instructions.