Is it possible guys? As I know I can use the React Native eusing Windows Laptop but I can't build or produce a mobile ios app using Windows laptop?
Also what are the conflicts when developing android app and iOS app using Reactive Native
You can develop your iOS and Android app completely on windows, but it is correct, that you need a Mac to build and deploy it for iOS app. You could use a service like https://www.macstadium.com/ for this step. They offer access to macs on a monthly basis.
I'm working with RN since 2015 and I only found a few "conflicts":
1.) You have to double check styling between iOS and Android, since a few properties behave little different (like overview). But the RN team is constantly working on this and it gets better and better.
2.) If you need access to native device functions like InApp purchase API, you have to find Libraries, which work on iOS and Android.
All in all RN is a very good framework for writing cross platform apps. You should give it a try :-)