Originally Posted by
Alain_A I am using the iPhone 7 on wifi here in this forum so I must have internet connection
Are you using the "app" for the App Store, the blue one? Or are you using a browser on the phone and trying to connect to either the app-store or itunes or something. It's not very clear. I have downloaded apps in the car, at a truck stop, in a restaurant, on a train, etc.. so I am confused what you're actually doing. Are you correctly signed into the app store in settings with your apple and/or iTunes ID?
Also you could be using your iPhone data to connect to this forum, you can surf websites over data too.