How do you display the viewcontroller and the main.storyboard side by side to create an IB Outlet.?

I uploaded a unity project to Xcode and keep getting a Command PhaseScriptExecution failed with a nonzero exit code error, and the build fails to build. Does anyone know how to fix this?

I have uploaded an iPad app to the IOS app store for submission, and I would also like to be able to put it on the MacOS app store. I have tested it using the mac simulator and the app is compatible with Macs. How would I upload it to the Mac App Store from Xcode?