Hi @Ano Acco ,
Site templates and site scripts are currently only supported by SharePoint Online. Channels are created in Microsoft Teams. You cannot create an individual channel from SharePoint Online. So you can create teams quickly with Templates in Microsoft Teams as a workaround. Please refer to the following steps to reach your requirement
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.