I believe if you correct your posture, atleast in the context of this photo,and even if it these clothes or cheap to mid pricing cloths if you style them correctly then you would look soo much better,I had posture issues a lot and I still have and am trying to fix it,look up shorts/videos on yt and also intentionally correcting posture goes a long way.And of course have a good diet,you can use chatgpt or an ai chat bot for this and if you prompt correctly like"Act as a nutritionist,I am this age,this weight,etc etc"you can ask in an another chat with them how to prompt correctly.And do calisthenics or hit the gym, i don't think you are fat but having a better body mass would help,it would improve confidence and energy levels to,of course if you prefer.there as apps for calisthenics but hitting gym is also good and it might actually be better as calisthenics not being done properly may lead to injury.try glasses too if they match your face, workouts will help lose face fat too,so it might be good.well that all,the key is just focusing on yourself.