Hi@Anonymous ,
This should help you out:
1. Add the "add a row into a table", for you select the sharepoint site as your folder and find it there.
2. Then add the values you want to add in the excel sheet.
3. Lastly insert the same values in your teams post via adding the dynamic content for each row value you update in each column.

Let me know how it goes 😄
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Best Regards
Heartholme