By accepting an RSVP, you let the creator of the event know if you will be attending, which then allows the event to be entered in your own calendar so that you can see it.
Click on theicon on the toolbar frame.
Checkmark the item and click on thebutton for the particular message you want to accept in the list of alerts.
Set your appropriate status for the RSVP and click.
The icon within Calendar now shows the added RSVP.
The RSVP icon can be clicked from any calendar view to see the status of all RSVPs.