How can you turn participants' camera on or off during or before a team meeting?

Disabling cameras of attendees is a feature that can be found under the option: meeting options.
This setting allows visitors to turn off their video. this can be very important during webinars for education and board meetings.
Disabling cameras not only prevents videos from being accidentally or randomly shown to others, but it also ensures that visitors' videos do not end up in recordings where regulations or codes of conduct apply.
How to switch off all cameras of participants during a Microsoft Teams meeting
Press meeting options during the meeting.

Then in, Allow cameras during meeting, uncheck the option.

How do I turn off all cameras before starting the meeting?
If you have an important speech planned, it is often a good idea not to give people the chance to chat, make gestures in video or make sounds. Below, I disable these 3 options to remove all the disturbances.
- Chat block in Teams.
- Disable video for participants.
- Switch off sound / microphone for participants.
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