You can reduce the bounce rate by having some interactive elements on the page that users can interact with. This could be a form, button, poll, video, read more option, toggles, next and previous page options, scrolls etc.
When a user will interact with any of these elements an event is called. The gap between the time of coming to the page and clicking the element will help to identify the time a user has spent. Even an interaction after 2 seconds will reduce the bounce rate to zero ‘0’.
The other option is to change the default session time. By default, the session duration is 30 minutes.
Please see the link to learn how you can change the session timeout and call events to reduce the bounce rate.