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Open the Team you want to create a channel in.
Click on the "More options" button (represented by three dots) located at the top of the left-side navigation menu.
Select "Add channel" from the drop-down menu.:
Enter a name and description for the channel.
Choose whether the channel should be public or private.
Click "Add" to create the channel.:
How to Participate in a Channel in Microsoft Teams
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Open the Team that the channel is linked to.
Click on the channel you want to participate in, located in the left-side navigation menu.:
In the channel, you can participate in conversations, access and share files, and collaborate on tasks together.
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