Thank you John! Unfortunately, there is no equivalent to didSelectAnnotationView in SwiftUI, yet. If you want to create such app, I recommend you to use UIKit for now. I also wrote this tutorial on Map view in UIKit, check it out:

https://medium.com/ios-design-code/create-a-map-show-users-location-xcode-12-swift-5-3-c5052949313f