Are there chills too with fever?
If yes then it can be malaria or dengue.
Dengue can also present with rash along with fever.
If the fever is not subsiding with medications then u should go for blood tests.
And take proper medications which might include antibiotics.
Next Steps
blood investigations eg cbc, psmp, widal, dengue igM
Health Tips
plenty of oral fluids, cold tepid sponging, adequate rest