Hey there @Mo7amad_22! Welcome to the community! Here’s a couple resources from different users as well as the official documentation and official video on the subject matter. Combining both should give you a solid grasp on how to handle DLC and prepare you for some of the hiccups that can occur during the process. Hope this helps!
Basic setup for Chunkdownloader and packing by Michael Prinke:
Jilted Games goes over how he handled DLC and patching in a linear fashion:
The official docs (which you have no doubt seen already but I have to include them):
Disclaimer: One or more of these links are unaffiliated with Epic Games. Epic Games is not liable for anything that may occur outside of this Unreal Engine domain. Please exercise your best judgment when following links outside of the forums.