https://www.fda.gov/

FDA is the abbreviation of the U.S. Food and Drug Administration, it protects public health by ensuring the safety and efficacy of a range of products, including human and veterinary drugs, biological products, medical devices, the U.S. food supply, cosmetics, and radiation-emitting products. It also provides the public with accurate, science-based health information. Since the passage of the Pure Food and Drugs Act in 1906, the FDA has been performing its regulatory functions, and it has been known by its current name since 1930.
 

FDA Organization

FDA is an agency within the Department of Health and Human Services and consists of nine Center-level organizations and thirteen Headquarter (HQ) Offices. 
FDA Organization Charts
 

Basic Laws for FDA Drug Approval

Chapter 5, Section 505 of the Food, Drug, and Cosmetic Act
Section 312, 314, and 514 of Chapter 21 of the Code of Federal Register

Types of Applications