I genuinely cant stand my side profile how do I fix it?

im an 18 year old, reasonable weight (68 kilo about 5'10 ish?) not that skinny but not that plump either yk? and now front on I'd say I'm alright looking but my side profile is disgusting, I have excess neck fat that gives me a double chin the second i look down, bad posture and overall i want my jawline to look better, you cant see it because of my disgusting neck fat and I hate it. please tell me this isnt forever.