Question

Explain thermal physics in details

Answer 1

You have to be kidding. The only thing you didn't include was to do in three short paragraphs.
You can start here:
https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/thermodynamics-17/the-laws-of-thermodynamics-123/the-three-laws-of-thermodynamics-496-3601/