Task and planners can't be used for private channels, which is a limitation of privacy channels. For more restrictions on private channels, see: https://learn.microsoft.com/en-us/microsoftteams/private-channels#private-channel-limitations.
All other channel types are available. To use tasks and planners in a channel, follow these steps:
- In your team channel, select Add a tab +.
- In the Add a tab dialog box, choose Tasks by Planner and To Do.
- In the Tasks by Planner and To Do dialog box, choose Create a new task list or use an existing task list.
- Choose whether to post to the channel about the tab, and then select Save.
For more details about using Planner in Teams, you could refer to:
https://support.microsoft.com/en-us/office/use-planner-in-microsoft-teams-62798a9f-e8f7-4722-a700.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.