Since GA4 launched, the bounce rate metric has been replaced with the engagement rate metric. This can be found as follows:
Open your GA4 property: Sign in to Google Analytics and select your desired GA4 property.
Choose the report you want to customize: Navigate to any report you'd like to view bounce rate within. For example, "Pages and screens" report is a popular choice.
Access the customization options: Look for the "Customize report" button in the top right corner of the report. If you don't see it, you might need Editor or Administrator permissions.
Add "Bounce rate" as a metric: In the right panel under "Report data," click on "Metrics." Scroll down or search for "Bounce rate" and select it. You can also add "Engagement rate" (the inverse of bounce rate) for further analysis.
Apply and save your changes: Click "Apply" to see the newly added metric(s) in your report. Consider clicking "Save changes to current report" if you want this customization to be permanent for this specific report.