Left-click and drag to pan and spin the view around.
Scroll the mouse wheel to zoom in and out. Right-click and drag up or down also zooms, or pinch on a trackpad.
Hold Ctrl and left-click and drag (or middle-click and drag) to tilt the camera and change the viewing angle.
Playback: the flight plays automatically. Use the round play / pause button in the clock dial at the bottom-left to start or stop it, and drag the timeline along the bottom to jump to any moment.