In order to be able to make a video reading, you must first enable your web browser to access the camera and microphone.
Find out how to handle it if you use Samsung Internet.
To access the permissions settings, click on your Samsung navigator (the 3 lines at the bottom right) and then on Settings.
Scroll down and click on "Sites and Downloads".
Click on the "Camera" and "Microphone" checks.
By doing so, you allow your browser to use the camera and the microphone.
If you are using another browser, please find further information here.