Go to the team site you want to create the additional calendar for.
Click on the “Gear icon”, and choose “Add an app”.
Choose the “Calendar”, you only need to pick a name, and finish the create process.
You can now start using your calendar.
You can access this calendar on the left hand side panel (where “announcements, calendar, contacts, etc” are at).
You can also add it to your front page if you wish, for quicker access, here is how.
Go back to the front page of your huddle site, click “Edit”.
Go to “Insert”, and click “App Part”.
Choose the calendar you just created, and click “Add” button at the bottom right corner.
Finally, click “Save”. Now you should see this calendar on your front page.