Integrated laptop webcams are very basic and do not have many settings available.
1
You indicate the room is well lit, ensure the light is in front of you, not behind or above you.
2
Then open the Settings app.
Go to Bluetooth and Devices - Cameras - Integrated Camera.
In there, there are sliders to adjust the Brightness, Contrast, Sharpness and Saturation on your webcam, try using those sliders to improve the image produced by your webcam.