Regarding existing tags in Google Analytics Universal, when setting up a new property with GA4, if the setup wizard provided the option to “Enable data collection with your existing tags,” you are likely already collecting data on the new property. To ensure this is happening, you can go to the “Real-Time” report and monitor the activity there.
If your site's pages are tagged with analytics.js, then the administrator investor database cannot use existing tags. In this case, you can add GA4 gtag.js tags directly to your pages.
Google Analytics 4 provides a series of organized reports that allow you to record and access relevant information about the entire customer lifecycle.
Acquisition Reports
This type of report provides data on how traffic reaches the site or application. It provides metrics on:
Number of new and returning users : These are all users who visit the page or application.
Number of sessions : These are collections of events that the user generates in a given time.
The source and medium from which the session arose : information is obtained from where the session was generated, for example, an advertisement.
Customer Lifetime Value (LTV) : This is the average revenue over the first 120 days.
Engagement or interaction reports
These types of reports allow you to measure engagement based on the types of events triggered by users.
Engagement metrics : These include the sessions described above, the time the app or site page is in the foreground, active users, engagement time, which is calculated based on engagement time and active users, and, finally, the average user interaction time.
Events: These metrics include when users purchase a product, submit a form, or view an item, among many other events that are recorded.
Conversions: This report stores events that were recorded as.