Dear Sir, Your son seems to be active and smart but at the same time you say that he is lagging behind in studies and does not behave his age. Also, he does not respect elders and also indulges into junk food. It seems that your son is having behavioral issues which needs to be addressed as soon as possible before it worsens. This could be due to number of reasons, it could be due to his age, the peer group, lack of discipline, over pampering, or very strict environment at home or school etc. It is not late, you can take your son to a clinical psychologist and get detailed assessments done to rule out conduct disorder.

Hello sir.... You can consult for this to any psychologist......and try to talk to him be a good friend of him and start talking like a friend......start morning walk for him.... And try to contact your near by psychologist of your area Thank You