what should i do to improve below code, i am new bee to unity, C#

I am a new bee to unity and C#, I have written ios swift unity wrapper. I just want to know can below code written in a better way, without breaking wrapper functionality.

Native.cs

[DllImport("__Internal")]
extern static public void SDK_getOffers(Action<bool,string> completionHandler);

ButtonHandler.js

[MonoPInvokeCallback ( typeof ( Action<bool,string> ) )]
static void completionHandler ( bool status, string message ) {
//         logs =   "✅ status is: " + status + "\n" + "✅ message is: " + message;        
}

public void ButtonGetOffersTapped() {
   #if UNITY_IOS && !UNITY_EDITOR
   UnityEngine.Debug.Log("✅ button get offers tapped");
   SDK_getOffers(completionHandler);
   #endif
}

is there a way to write completion handler with along with function itself, rather then writing as separate function?