Thank you for your query,
Your son fever could be due to a infection caused by the dog bite with the pathogens present in dog oral cavity and this infection to be treated with antibiotics like oral amoxicillin and with a antipyretic like paracetamol
Wash the area of the bite with soap and under running water and check for his immunization
status for Tetanus and if it is not appropriate Tetanus toxoid injection
should be taken.
The most important thing is to take the post exposure prophylaxis against the rabies by taking anti rabies vaccination
according to the schedule on 0, 3, 7, 14, and 28 days.
So consult your Pediatrician
immediately for the appropriate advise and for the appropriate management of the dog bite.
Hope I have answered your query.