For fever syp calpol is ok.. n give him as per requirements. Don't feed him forcefully as due to infection he is feeling nauseated. If not taking ORS can give him other liquid diet..like plain water, rice water, or dal ka pani.
Next Steps
give him syp zincolife 2.5ml twice a day
enterogermina once a day
Health Tips
watch urine out put... n he shouldn't be lethargic