When using the mobile app, you will see the button with the calendar icon and a number next to it, indicating the number of events you have today. When you tap on it, a new panel will open up showing you these events.
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If this is the case, then your buttons are most likely hidden from the main view. To show them, tap on the ⋮ icon on the top-right and there you will see the "Show buttons" option where you can toggle the visibility of these buttons.

Related article:

- How to show or hide buttons in the Today view