in a table i have columns that 1 want to add together and i can’t do it
Writer or Calc?
… or base? 
Hello,
in this example assume you have your numbers in first colum and 9 rows are filled (cells A1 through A9)
LibreOffice Writer Table: put =SUM(<A1:A9>) in cell where you want to have the sum.
LibreOffice CalcTable: put =SUM(A1:A9) in cell where you want to have the sum.
(Please don’t ask why the syntax is slightly different in the applications)