Currently quite time for NEET Preparation. I suggest followoing step for NEET preparation:

1. Cover Each Syllabus Topic:

Physics

• Physical world and measurement
• Kinematics
• Laws of Motion
• Work, Energy and Power
• Motion of System of Particles and Rigid Body
• Gravitation
• Properties of Bulk Matte
• Thermodynamics
• Behaviour of Perfect Gas and Kinetic Theory
• Oscillations and Waves

Chemistry

• Some Basic Concepts of Chemistry
• Structure of Atom
• Classification of Elements and Periodicity in Properties
• Chemical Bonding and Molecular Structure
• States of Matter: Gases and Liquids
• Thermodynamics
• Equilibrium
• Redox Reactions
• Hydrogen
• S-Block Element (Alkali and Alkaline earth metals)
• Some p-Block Elements
• Organic Chemistry- Some Basic Principles and Techniques
• Hydrocarbons
• Environmental Chemistry

Biology

• Diversity in Living World
• Structural Organisation in Animals and Plants
• Cell Structure and Function
• Plant Physiology
• Human physiology

2. Review the last 10 years question and papers which would be given an idea about the exam pattern.

3. Do practice on sample papers which would be helpful to judge NEET preparation.

4. Attempt online mock test series such as EtoosIndia VMTS Test series which would be helpful for you to clear each doubt.

5. Watch online video lectures from reputable online institute like EtoosIndia and more so you can give more time for exam preparation because online video lecture saves your money and time also expect offline institutes.

6. Follow best NEET faculties video tutorials

Hello,

Here is the list for the important chapters with high waitage

For biology it's divided into two that is zoology and botany starting from zoology

Zoology - human reproduction , evolution, immunity, animal kingdom (only from NCERT) 

Botany- plant kingdom, organisms and population, ecosystem, plant reproduction biological classification

This are some very imp chapters with high waitage of biology . Coming to physics and chemistry.

Chemistry- organic (very imp.) , Solutions , chemical bonding (again very very imp) electrochemistry , chemistry in daily life ,.NOTE - do not ignore inorganic chemistry it makes difference during the exam

Physics- laws of motion (v imp) { not many questions ask from this chapter but it's the basic for all the physics chapter don't ignore it} ,,,, optics , work energy and power, electrostatic , current energy 

Hope uh are clear now all the best for ur exam

The entire chapterwise weightage given below for 11th grase syllabus for NEET UG and based on top weightage you can decided all important topics. 

https://medicine.careers360.com/articles/neet-chapter-wise-weightage-and-important-topics