I never download presets/samples so I don't know if you can find any of those
if you don't know how to work with FM synths and modulation try something else that you know better like massive or whatsoever
choose a SAW wave
use a LOW PASS FILTER until it sounds something warm like an ORGANO maybe
then make the envelope the way you like it : flutes don't have too much attack so you have to reduce the attack, more attack sounds like ORGANO less attack sounds like FLUTE
and a second synth for the WHITE NOISE to give that air kind of sound that flutes have
than try EFFECTS like TREMOLO, CHOURS, REVERB, DELAY ; and make it sound the way you like it
that is all you need to do you need to get used with these kind of things if you want to make sounds the way you like it otherwise you will simple search the presets you have