Hi @Arif, Laiba
To my knowledge currently there is no built-in feature in Teams to automatically add an app to new channels.
I suppose you may have a look at Power Automate and Graph API to archive this.
Here is a link which may be helpful: Adding Power App To Teams Tab Using Power Automate
(Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.)
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