The statement says "declare" a function... but i think should be "defining"

Question

difference between declaring and defining

Answer 1

function declaration includes only type of function, its name and types of arguments, while the definition describes the logic and behavior of function. for example, "int sum (int a, int b);" is declaration, and definition of it will be later, for example, as "int sum (int a, int b) { return a+b; }"

Answer 2

declaring a function is saying there is a function.
defining the function is saying how the function works.