Use the property selector or Admin to navigate to your new GA4 property.
1. Click Admin.
2. In the Property column, check that you have your new Google Analytics 4 property selected, then click Data Streams, then Web. ...
3. Under Tagging Instructions, click Add new on-page tag and look for "Global Site Tag (gtag.js)".
Add a Google Analytics 4 property (to a site that already has Analytics) support.google.com › analytics › answer
There's no cost to have tags running on your website or apps, and Analytics 360 customers will not be double-charged for Google Analytics 4 hits, though eventually there will be an Analytics 360 version with increased functionality and/or limits.
What you need to know about Google Analytics 4 (formerly ... - Cardinal Path
www.cardinalpath.com › blog › what-you-need-to-know-about-google-ana...
However, we highly recommend that you upgrade to Google Analytics 4. As mentioned above GA4 provides a much better data model than the current version of Google Analytics. You don't have to use GA4 for your reporting and analysis right away but it will give you an option to try out new things.
Should You Upgrade to Google Analytics 4 (GA4) - Optizent
www.optizent.com › blog › should-you-upgrade-to-google-analytics-4-ga4
merging properties is not possible. For future reference, if you change your website again and keep the domain, rather than craeting a new property, keep the same Property and tracking code and put it in the new site pages.
How can I merge two properties? - Google Analytics Community
support.google.com › analytics › thread › how-can-i-merge-two-properties