Forcing the camera to portray a specific rect at all times

I have a game with a static camera in which there’s an arena that players play in. I’m working in 16:9, but with some aspect ratio (heck, even 16:10 cuts a bit the sides) a part of the arena is out of screen.
Is there a way to make sure that the camera ALWAYS portrays the part I’m interested in?

Yes, you have 2 options, or move the camera position, or change the camera rotation.

Go look for tutorials about this issue.