need to write small c# code to merge data from duplicate columns but with different values in excel and create datatable

need to write small c# code to merge data from duplicate columns but with different values in excel and create datatable

Timestamp Amount [lb] Dupcol1 Dupcol1 Dupcol1 anothercolumn
Mar 15, 2023 at 5:23:52 PM CDT 45 426 9 10,655 2,318
Mar 15, 2023 at 5:12:59 PM CDT 55 426 9 0 0