So sorry to hear your child is not well. There are many viral infections doing the rounds aajkal.
Most viral fevers should get better by day 3-4. So symptom relief is primary- you can give calpol/Crocin/paracetamol upto 4 times a day and if fever comes in between doses you could also give Meftal P upto three times a day in between.
For cold/runny nose other combination medicines can be given if needed.
Appetite will be low, give fluids/semi solids
Next Steps
Continue regular medicines for fever and cold
If no improvement by day3-4, see doctor/consult for possible blood tests to rule out other less common conditions
Health Tips
Tips-
Fever control regularly as mentioned above
Hydration is important
Seek urgent help if lethargic even when temp is 4days with no sign of improvement