Hey Gopal Dubas,

The entire syllabus, exam pattern, online application form, exam dates, best books for biology, physics and chemistry are given in The following link,

https://medicine.careers360.com/articles/aiims-mbbs-2019/amp

the important topics in physics are:

Laws of Thermodynamics

Ray Optics

Rotational Motion

Semiconductors and Communication System

Photoelectric Effect and Electromagnetic Waves

Current Electricity

Electrostatics

Waves and Sound

Electromagnetic Induction and AlternatingCurrent

Magnetic Effects of Current

the important  topics in chemistry are:

Classification of Elements and Periodicity in Properties

General Organic Chemistry

p Block Elements

Atomic Structure

Chemical Bonding and Molecular Structure

Carbonyl Compounds (Aldehydes and Ketones)

Solutions and Colligative Properties

Ionic Equilibrium

Chemical Thermodynamics

d and f Block Element

Haloalkanes

the important topics in biology are: 

Biological Classification

Plant Kingdom

Morphology of Flowering Plants

Cell – The Unit of Life

Digestion and Absorption

Chemical Coordination and Integration

Sexual Reproduction in Flowering Plants

Human Reproduction

Principles of Inheritance and Variation

Human Health and Disease

Ecosystem

Environmental Issues