Hi @Peter Urs
Currently, Teams does not provide the function of directly creating file templates. To get this feature more quickly, you can send a feedback directly to Microsoft Feedback to add it in future updates.
Many features of our current products are designed and upgraded based on customers’ feedback. With requirements like this increase, the problem may well be released in the future.
You need to manually save the file as a template file after creating it.
1.To save a file as a template, select File > Save As.
2.Double-click This PC.
3.Type a name for your template in the File name box.
4.For a basic template, select the template item in the Save as type list. In Word for example, select Word Template.
5.Select Save.
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