Here is an excellent post on RTI in children and that includes URTI LRTI. What is important is use a severity based plan. Well children do not need antibiotics.
https://dontforgetthebubbles.com/respiratory-tract-infections-children/

Respiratory Tract Infections in children

Emily is a 2 year old girl brought to the emergency department with her mum, following two days of fever and poor intake. She has a temperature of 39°C and ….