No calendar in Teams

I don't have the Teams calendar app and I don't see how I can install it.

We've tried to use the admin account, but we just don't see the calendar.

So we contacted Microsoft, they tried to help us. They managed us to the admin center, to go to users but we don't see any of our users in our Team.

So we still don't see the calendar.

They said to find help on this platform

Can anybody help us 1) to find the calendar (no ouutlook) 2) to find our users at the admin center.

thanks