From Black to HeartGold, no.
Poke Flute Just a radio channel that only Kant uses Black Flute Repels wild Pokemon White Flute Attracts wild Pokemon Blue Flute Awakens a sleeping Pokemon Yellow Flute Snaps a Pokemon out of Confusion Red Flute Snaps a Pokemon out of Infatuation
The PokeFlute is used to awaken Snorlax.
at the kanto radio tower
Lake of Rage.
update your radio It'll be the middle line on your radar at the top
you can transfer it from Pokemon soulsilver/heartgold to Pokemon black
You can transfer Pokemon, but you can't trade. Since HeartGold was released before Black, HeartGold doesn't know Black exists. However, Black knows HeartGold exists. You need to be on Route 16 in Black version, which requires beating the Elite Four.
ask the little children they know you want them
You don't get a pokeflute. It is an option on the kanto radio receptor.
you have to beat the elite four than talk to professer elm he will give you the poke flute