Add Files to MS Teams Channel

Sharing files in a private channel in Teams. 

Issue

Share files with only members in a private Teams channel. 

Open Microsoft Teams.
Select the Team and Channel.
Click the Files tab.
Select Upload > Files.
Choose your file and click Open.

You can also drag and drop files in a private channel.

Open the channel’s Files tab.
Drag a file from your computer and drop it into the Files area.