You can access every row with an index like this: %OutputDt[RowIndex]['Id']%.
The index for the last row will be equal to the count of total rows in the table minus 1 (as indexes are 0-based in PAD). A data table has a property called .RowsCount that contains the number of rows in the table. So, you can do %OutputDt[OutputDt.RowsCount-1]['Id']% to get the value from the last row in the column named 'Id'.
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