Who believes in aliens?

whoever belives in aliens are strange but not....like many people will say well there isnt anything and its just your imagination....IF there is aliens...how would they get to earth...? How would they find metal like material and make UFO'S and FLYING SAUCERS? And how do they breath everything has to breat...we breath air...fish breath water what do they breath...I'm 14 I may not know everything....but for the people who swear they have been ubductedx go ahead think that but then listen to it...how do they come to earth...lets say they do breath something...we breath air but we cant breath water so how would they be able to breath what we do...it just doesnt make sence....every night i see a star that moves in a L shape all of mii friends I have shown them theyve seen it too...thats what got me thinking but really how would they make a UFO and make it fly? SERIOUSLY