Fine
Create a datatable with a single column using build datatable activity
—then if this string is stored in a variable named strinput
Then in a assign activity arr_str = Strinput.Split(Environment.NewLine.ToArray())
Then use a FOR EACH activity and pass the above array variable as input
—inside the loop use ADD DATAROW ACTIVITY and in ArrayRow property mention as {item.ToString} And in datatable mention as dt
Now this dt will have those values in each row one by one