Excel's Insert Function dialog box and Formula palette make it easier for you to use and understand functions by organizing them into logical categories and by prompting you to complete the arguments required to make the function return a correct value.
The Insert Function dialog box and Formula palette can be accessed in several ways:
Click the Insert Function button (the fx button)) on the Formula bar.
Click Insert in the menu bar and choose Insert Function.
Type the equal sign (=) and name of the function in a cell and press Ctrl+A. Then enter the arguments in the Function Arguments dialog box.
Click the Function down arrow button at the far left end of the Formula bar and ...