Build IPA file and upload to app store

I need some help in building and submitting an iOS app to the App Store. I have an existing Apple Developer Account, and I want the develop to provide support services for the App Store submission. The project requires that a valid IPA file is generated with all requirements met and uploaded to the App Store for review. I only need for this project for the iOS platform and no other platforms.

The app is in 3 components; delivery, restaurant and user app.