Camera directing for lenghty single character scene talking
There are two main things you want to do here.  First, use a lower camera angle for your main camera.  You are shooting from substantially above your speaker which makes them seem diminished and small, but you want them to be the focus of attention.  Shoot from eye level or slightly below eye level to give them a feeling of more importance in the scene.

Second, use multiple camera angles.  You can easily break up a long scene with one speaker by cutting between multiple angles of the same individual.  Be aware of the axis of action however.  You don't want to have your left and right sides get suddenly reversed, but cutting between a close up of them talking vs a wide shot or a mid shot from a different angle can help the video feel less static.

As far as an example of this in action, look at any kind of news or public speaking footage (such as political debates or church sermons).  You will see a variety of different camera angles to try and methods and timing of cuts to help make the footage feel less static from these kinds of sources.