3 Camera Tips

If you want the camera to match what you see in the viewport, press Alt+Ctrl+0.

This will move the camera to match what you were seeing in the viewport.

To change the active camera, select the camera you want and press Ctrl+0.

When you render it will be what the active camera sees.

Check the box next to "Lock Camera to view" to be able to move the camera view much like the viewport.

This is a quick and familiar way to reposition the camera.
You can add this checkbox to the Quick Favorites for easy access.