iTunes Connect
https://help.apple.com/itunes-connect/developer/ — equivalent to Google Play Developer portal. iTunes Connect is more difficult to use than Google portal. It will take more time than the Google portal to figure out what you are supposed to do.
After filling out the registration form, you will be taken to the app's dashboard. Here you need to provide more metadata about your application. Then you need to upload screenshots with your app interface — for the biggest iPhone and iPad screens. Screenshots could be done on a physical device or using an iOS simulator. When it will be done, you need to work with your .ipa file. There are many ways to do that. You could use XCode, Application Loader, NativeScript CLI. Publish your app with the command tns publish ios --ipa <path to your ipa file>. Your app becomes available for up to one hour.
Publishing your app in stores requires a lot of time and some background experience. That's why we strongly recommend to contact us or leave your contact information.
Wish you good luck in programming!