Plist files are basically XML files. Either you use Xcode to edit it or you will need to use a text editor to edit the raw XML.
Alternatively, you can use Cocos Studio to design your level. However, unlike Unity, you can’t actually directly attach a script to the Nodes in Cocos Studio. I am not sure about LUA or JS but at the very least, you need to improvise for C++.
What I would recommend is to build your levels using the Studio then when you load the levels in your code, you use the ComController on your Nodes. Further information can be found here: Subclassing cocos2dx::Sprite