Once you’ve customized a report, where does it need to be added to in order to appear in the left-hand navigation?

In Google Analytics 4 (GA4), once you customize a report, it needs to be added to a "Collection" to appear in the left-hand navigation. Collections are customizable sets of reports that you can organize to suit your analytical needs. By adding your customized report to an existing or new collection, it becomes accessible directly from the navigation menu. "Admin" is where you manage settings for your GA4 property and account, not where you organize reports for navigation. "Library" is where you can find and manage all your reports, including custom ones, but merely having a report in the Library doesn't automatically add it to the navigation. "Explore" is a separate section for advanced data exploration and analysis, not for organizing standard reports in the navigation.