how to lose belly fat?

its not like im fat..i just have a little bit of fat on my belly.

people say crunches and sit ups dont do anything but form the abs, and i want to know specific exercises that get rid of the fat on top of the abs.

for how long should i do the exercises and when should i expect to see results if i do them constantly?

also, how do i lose flab on my arms? thanks :)