IPhone : How do I combine several SpriteKit projects into one?

I wanted to create a game, so I made about 6 different SpriteKit projects each containing one of the scenes eg. the start scree, the easy difficulty screen, etc. Now, I want to compile all of them in one single SpriteKit project. I searched about this for about 2 hours. Many people suggested using Workspace, but I cannot pass values between different workspaces.

I even tried making another fresh SpriteKit project and adding all the code of different projects into different scenes, but by doing that, all the other added scenes in the project got sorta wrapped.

I create SpriteKit Scenes by (command + n) > CocoaTouch Class and select SKScene as Subclass.

So, is there any way in which I can compile all of my projects into a single one? If using Workspace is the only way, can you please elaborate on how to use it to pass values and presentScenes in it from different projects?

Sorry for the long post, I am a real noob, any kind of help will be much appreciated and do let me know if you need some more information to provide a solution.

Thanks!