The first thing you will want to do
is open the calendar app on your iPhone
and find the event you wish to delete.
You can find the event in two ways:
You can tap on the date where the event takes place,
or use the search function
at the top right of the screen
to find the event name.
Once you are on the event page,
tap "Delete Event" at the bottom.
If it is a recurring event,
a pop-up window will appear to confirm
whether you want to delete the entire series
or one single occurrence.
Tap "Delete All Future Events"
if you wish to delete all future occurrences.
If you wish to delete only this instance of the event
and still want the next occurrence
to appear in your calendar,
tap "Delete This Event Only" instead.