Both cordova and xamarin have their pros and cons. We don't know anything about your project or what you are trying to accomplish so the only thing we can suggest is try both and see what you like.
Cordova is more a web technologies framework for building cross platform mobile apps and xamarin is .net framework geared more towards building native cross platform apps. I have severely trivialized this but that is simplest way of putting it.
I suggest your do further research and evaluate what best meets your needs as only you know what your projects requirements are.
Xamarin vrs cordova- Google Search[
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