Hi Mehrdad,
You can simply add the control to your project (e.g. you can create a new folder "MyControls" and copy the control's code files in there) and create a new web part which will utilize this control according to Developer's Guide - Developing web parts.
However, we do not have any built-in Persian calendar web parts so implementation is up to you or if you need some help and guidance, you can use our Consulting Services (consulting@kentico.com).