1. Open Chrome .
   

2. Go to a site that wants to use your microphone and camera.

3. When prompted, choose Allow or Block.

   1. Allowed sites: Sites can start to record when you're on the site. If you're using a different Chrome tab or a different app, a site can't start recording.

   2. 
      

   3. Blocked sites: Some sites won't work if you block them. For example, you won't be able to join a video conference

Change a site's camera & microphone permissions

1. Open Chrome .

2. At the top right, click More Settings.

3. Under "Privacy and security," click Site settings.

4. Click Camera or Microphone.

   • Turn on or off Ask before accessing.

   • 
     

   • Review your blocked and allowed sites.

   • 
     

   • To remove an existing exception or permission: To the right of the site, click Delete .

   • 
     

   • To allow a site that you already blocked: Under "Blocked," select the site's name and change the camera or microphone permission to "Allow"

Allow Hangouts Meet to access your camera and microphone

Before you start using Meet, you will need to allow access to your computer's camera and microphone.

Allow access the first time you use Meet

1. In a web browser, go to the Meet homepage.

2. Click Start a new meeting.

3. Click Allow.

Change the setting to allow access.

If you aren’t asked to allow access or if you blocked access before, you can change your settings.

1. In a web browser, go to the Meet homepage.

2. Click Start a new meeting.

3. At the top right, click Camera blocked .

4. Click Always allow https://meet.google.com to access your camera and microphone.

5. Click Done. The video meeting automatically connects. If you don't see the meeting reload, exit and re-enter the meeting.

From Google Meet Help.  For more information -- https://support.google.com/meet/answer/7317473?hl=en