I've been trying to use react-ga package with google analytics 4 in my app. The measurement id doesn't work with it and there is no tracking code in google analytics 4 I can use. Please, I need help!
import ReactGA from 'react-ga';
const trackingId = 'G-XXXXXXXXXX'; // UA-XXXXXXXXX-X isn't available in GA4
ReactGA.initialize(trackingId, options);
ReactGA.pageview(page);
The code you entered in the example, G-XXXXXXXXXX
, refers to the new Google Analytics 4 which, being a different system from the previous one and does not work (yet) with that plugin.
So you can follow the instructions mentioned in the answer of @Shyam or (and I suggest you because GA4 is too unripe at the moment) create a Universal Analytics type Property and use its ID (UA-XXXXX-X) with the plugin you indicated. You can find it by clicking on Show advanced options
(when you create a new property):