To view Calendar click on Calendar from left sidebar. In this module you can see the Quotation, Invoice, Purchase, Projects, Tasks and Event with its name and can also see in which date its created by clicking on the checkbox button and you can also it individually or all together. If you click on any name then it will take you into the details page of it.
To create an event click on the date in which date you want to create an event from Calendar.
To edit an event click on the event from Calendar.