All items on a Moodle course with dates (e.g. due dates for assignments) appear automatically in the Moodle calendar for that course. Each user will also see a combined view of all their calendar entries within their My Home page. This shows all events across all the Moodle courses students and staff are enrolled on.
The Moodle calendar can be accessed by clicking on the month within the Calendar block, or clicking Go to calendar... / New event... at the bottom of the Upcoming events block.
This guide is in development. For now please see: https://docs.moodle.org/26/en/Using_Calendar