Fix my Beta App on iOS

there is a well implemented cloudkit app that uses apples cloudkit access to build this app. The app Is in Swift and there are a full page of fixes that need to go into this project. I want to keep the app I have and build on it and fix it. Please have current swift, cloudkit (apple database), Developer.apple.com ( to upload my app to my account)(I only have an individual account). I will allow you to log onto my Apple ID to work on and upload app to the App Store. It requires a 2nd verification I will have to send you. This is how we did the beta app with the developer after him not specifying what apple account to purchase ( one reason why Im getting a new developer)