1. Tap and hold a day where you want to start the events or you can also tap a day and tap the add event button.
2. If you use the app with the Natural Language Input(it can be off in the settings page), it will not show the recurring button at first since the keyboard hide it. In this case, slightly swipe up the page to hide the keyboard which is hiding the buttons.
And tap the rounding 2 arrows button at the right bottom corner.
Or you can tap the "Show More Details" to show the buttons like below.
3. Simple repetitions are listed in the Quick tab and you can make more complicated one by moving another tabs(daily, weekly, monthly and yearly) and adjust the details of the recurring options.