Solution 1:

This is what you can do. Firstly, you can initialize and export navigationRef from the file in which you've NavigationContainer.

// App.js
    
import * as React from 'react';
import { NavigationContainer } from '@react-navigation/native';
import { navigationRef } from './RootNavigation';

export const navigationRef = React.createRef();

export function navigate(name, params) {
  navigationRef.current?.navigate(name, params);
}
    
export default function App() {
  return (
        <NavigationContainer ref={navigationRef}>{/* ... */}</NavigationContainer>
  );
}

then you can import it in which you've PushNotification.configure()

// notification-service.js

import PushNotification from 'react-native-push-notification';
import { navigationRef } from './App';

/* Your other code */

PushNotification.configure({
  onNotifications: (notification) => {
  
  // Now you'll have access to the navigation object's function here...

  }
})

You can get more clarity from the docs here: navigating-without-navigation-prop