What is the syntax for the SUM function?

You have the equals, the name of the function, an open bracket, what you want to sum and then close the bracket. Usually it is a range in the brackets, but it could be individuals cells or numbers. So to sum the cells from F6 to F9 we could do it different ways. The proper way is the first of the two examples, but it could be done the second way too, though nobody would do it that way.

=SUM(F6:F9)

=SUM(F6, F7, F8, F9)