What kind of dumb question is that it is not a dumb question! i don't know how to whistle either! this is how you wistle you poke your tongue out of your mouth and blow really hard bite your tongue OUCH see you can wistle
Take your right hand and keep the thumb finger perpendicular to fore-finger. Now keep your mouth between thumb and fore-finger where the fore-finger touches the forehead and the thumb the lower jaw....
by seeing their adults of course but most of them are natural instincts with animals... no one needs to tech fish how to swim they know what they want and they naturally do it.