You must have Xcode and CocoaPods installed.
More instructions here
you must install CocoaPods through brew instead of through the gem
After you install the CocoaPods, you need to cd ios > app and then pod install
Then you can cd to Core-PWA root directory again and run the project using npx cap open ios or just double click on the workspace file located in ios > App > App.xcworkspace
You can also run yarn ios-run