Add Repetition Pattern is located under My Calendar > Add Event > Repetition Pattern. Repeating events have identical event details except for their dates and times.
Add Event screen.

Supported Repeating Patterns
Events can be repeated daily, weekdays only, weekly, monthly by date or day of the month, or yearly. Monthly by day does not support editing the pattern frequency. When using the “Monthly by day” period, the date repeated will be the starting date you select for your event. If you start an event on the 2nd Tuesday of the month, then monthly by day will produce an event occurring on the 2nd Tuesday of each month until the chosen “Repeat Until” date.
Example: daily repetition
Frequency: 1
Period: Daily
Repeat Until: 2021-11-12
Start date: 2021-11-05

The event will be repeated from the initial selected event date of e.g 2021-11-05 and up to 2021-11-12. Results in 7 events on the front end, but only one event to edit in the back end.

Changing Pattern Frequency.
Here is another example. This time changing the frequency from 1 to 2. As the notification says: “Every 2 weeks until 2021-12-04”. The frequency is the number of times the selected period will occur between each repetition.

The event is repeated every second week until 4th of December.

Edit event screen
After adding a Repetition Pattern in the Add Event screen, one can modify the dates in the Edit event screen. Here is the example from earlier with a daily event from November 5th until November the 13th. By clicking the View scheduled dates I get an overview of each date the event will be held. I can Delete or Edit en event and even add another date.

This makes it very flexible to use Repetition Pattern in the Add Event screen and then following up in the edit event screen to modify the event dates. One can totally change the repeated dates for the specific event.
Scheduled dates are not seen in the back end event list, as these are all linked to one event. The events are only seen in the View scheduled dates in the back end and as regular events in the front end calendar.
Read more about repeating events using an example with Add Copy and a Repetition Pattern.