Dear @Atar Sukamto,
Thank you for posting your question in the Microsoft Q&A forum. I understand the frustration of receiving too many notifications when you only need to track a specific subfolder. The "Create a rule" feature in SharePoint is designed to be simple, but it currently applies to the entire library by default, even if you have a folder selected.
To achieve folder-specific notifications, I recommend using the "Alert Me" feature, which allows for much more granular filtering than the standard automation rules. The most reliable way to limit notifications to a single subfolder is to create a specific "View" for that folder and then set an alert for it.
Step 1: Create a Filtered View
- Navigate to your SharePoint document library and open the specific subfolder.
- Click the View options menu (usually says "All Documents") in the top right and select Save view as.
- Give it a name (e.g., "Subfolder Updates Only").
Step 2: Set the Specific Alert
- With that subfolder still open, click the three dots in the top menu bar.
- Select Alert me.

- In the configuration window, look for the "Send Alerts for These Changes" section.
- Select "Someone changes an item that appears in the following view" and choose the view you just created (e.g., "Subfolder Updates Only").
- Click OK.
For more details and step-by-step instructions, please refer to: How to create Rules on a List or Library | SharePoint Maven
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If you need even more control, you can create a simple flow in Power Automate
As our current forum primarily supports Microsoft 365 products, and your issue relates specifically to Power Automate (Microsoft Flow), we recommend posting your question in the Microsoft Power Automate Community for expert assistance. The reason I ask you to post a new topic is that in the Answers forum, we have limited resources and very little knowledge about Power Automate, and in Microsoft Power Platform Community Forum Thread, you'll get the most qualified group of respondents, and other partners who read the forums regularly can share their knowledge or learn from your interaction.
The reason for this redirection is to ensure you receive the most qualified support and avoid any incorrect information. Members of that forum, including Microsoft experts and partners, regularly share solutions and best practices for scenarios like yours.
For more details on managing alerts, you can refer to: Create an alert to get notified when a file or folder changes in SharePoint - Microsoft Support
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