Health Medical Homework Help

I need an explanation for this Health & Medical question to help me study.

A.What are the main health problems and causes of death today in developed countries? Why have infectious diseases started to become an issue in recent times (such as the COVID pandemic)? What role does psychology play in these health issues and health behaviors

B. How do these issues play our in our (or your) everyday lives? Why have these factors come about and what can we do to reduce them?