It would be possible to add a control in the Calendar's footer template, but this is not a good idea because it is initialized on PreRender and only basic controls such as buttons and similar will function in it. That's why my suggestion is to place and configure the controls outside of the calendar.
As to your other request: Please, take a look at the following Multi-Month View demo
, which demonstrates how to configured RadCalendar to show more than one month in the calendar area.
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