As you know Teams is heavily used for team collaboration, letting users the ability to have group conversation, share files or even integrate with applications like Planner or third party like Jira or many others.
Well, there was still one piece missing on this collaboration space: shared calendar.
Good news, you can now add shared calendar on a Teams channel.
To add a shared calendar, go to the Teams channel you want to add a shared calendar and click the + (plus) sign to add a new tab
Then search for channel calendar
Then name the calendar to complete adding the new tab