You can put an if activity inside the for each loop and check if the row value equals 0 and if true then put continue activity in then block which will continue to the next row and put the required activities in the else block.
A better way should be to filter your dt and remove all the rows that contains 0, once filtered you will loop just through the rows you want without making validations within the for each row, you can use the filter datatable activity or else this linq code
Use Read Range activity to read the excel file with dt_Input as the output.
Use assign activity:
dt_New = If(dt_Input.AsEnumerable
Where Not (d(βAmtβ).ToString.Trim.Equals(β0β)).Any,
dt_Input.AsEnumerable Where Not (d(βAmtβ).ToString.Trim.Equals(β0β)).CopyToDataTable, dt_Input.Clone)
NB: dt_New is of type datatable.
Use it to collect output datatable that has filtered out Amt with 0.
This works either there are rows where the column Amt have 0 as value or not.
Write Range activity and pass dt_New as the datatable to write.