Lost my calendar when signing out. How do I restore?

Hello, I was prompted to change my apple id password. Did so and it created a sh*t show. My work computer's imessage wasn't working because of it so I then thought I'd just sign the whole computer into my apple id. In doing so got rid of my entire calendar. How do I get it back? I re-logged into what I thought it was before but nothing.

How do I get it back? I tried restoring from icloud preferences but still nothing.

Help!