Cough, sore throat
and high temperature with streptococcus
as an etiological agent can be managed well with penicillin.
In some cases there may be penicillin resistance, amoxicillin clavulinic acid combination works well in this condition.
Do warm saline gargle 3-4 times a day. For controlling temperature give paracetamol
6 hourly, also do tepid sponging.
As chest is clear it seems upper respiratory tract
infection. You can use some cough syrup to relieve cough.
Get a blood report done which will help in making diagnosis and also for assessing severity.