If you are designing a Numbers spreadsheet to give users who let them enter values, you may want to prevent them from entering values outside of a range . You can use conditional highlighting to change the color or style of a cell if the user specifies a poor value. You can use a formula in another cell to indicate a poor value, plus instructions. You can also use sliders, steppers and popup menu cell formats to limit values.
Check out guide users to enter correct values into YouTube spreadsheet numbers for closed captions and more options.