You can turn on the lights and even dim them through the Google Home App. I haven't left them on for very long but I'm certain they'll stay on until you turn them off.
In the picture I've attached, you can see the Camera and Flood Lights (labeled Pool) separate. If you click on the camera, it brings up the camera view. Depending on where you click on the Light, it either turns on the lights or brings up the option to turn to it to all certain percentage.