This forum does not come with a calendar by default, but a great modification exists.
To add to the calendar, create a thread about the event, then at the top right of that thread you should have "Thread Tools"
Click/tap on it and you should see this:

Then "Calendar Add" and it will then ask you for a date!
To add to the calendar, create a thread about the event, then at the top right of that thread you should have "Thread Tools"
Click/tap on it and you should see this:

Then "Calendar Add" and it will then ask you for a date!