Re: How to add document library attachment to list on SharePoint
Hi @Blurryface
Follow the steps below
1. I had used the trigger 'When a file is created or modified'
2. Add the action 'Get file content using path' to get the contents of the file. For the 'File Path' property pass the 'Full Path' from the above trigger action.

3. Use the action 'Create Item' to create the item. For title choose 'Name' property from the trigger condtion.

4. Add the action 'Add Attachment'. Choose the following properties
1. Id - Choose the ID from the 'Create Item' output.
2. File Name - Choose the 'File name with extension' from the trigger output.
3. File Content - Choose the output from the 'Get file content' action added in step 2.

Hope it helps, please like it or mark it as a solution if it resolves your clarification or issue
-Sudharsan K...