Hi @sunithav,
It is impossible to delete the row in which every column is blank because when Flow perform delete a row action could not find the key value of the key column, it like delete an item in a SharePoint list should get Item ID, it has no ID of the row, so it can be deleted.
As a workaround, you can create a new table (call it table 2) with the same columns as the original table (I call it table 1).
Table 1 - table need to process:

Table 2 - run result:
After process you can delete the table or keep it just you like, I hope it can help you.
Best Regards,
Community Support Team _ Lin Tu
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