The most important thing is "11. Process of preparing tea" without that even if all ingredient is present one can not prepare tea.
The same thing is in the case of Health!
Driving a 4 wheeler requires understanding the functionality of clutch, brake, gear system, accelerator, reverse, taking turns, traffic rules, various signals, oiling, greasing, regular servicing, etc.
The body is a machine, managing it requires an understanding of:
Own body type & its constitution,
Type of food one is eating,
Understanding the impact of seasons on eating food & lifestyle.