hello smriti mishra,

the following concepts are very important in jee mains and advanced which are having fundamentals in +1 board syllbus,

maths:

• permutation and combinations
• limits
• derviative
• quadratic equations
• straight lines
• sets and functions
• probability
• ellipse/hyperbola/parabola

physics:

• laws of motion
• gravitation
• work power engery
• circular energy
• rotational dynamics
• fluid dynamics
• waves and oscillations

chemistry:

• equilibrium
• mole concept
• atomic structure
• thermodynamics
• chemical bonding
• states of matter
• periodic elements

all the best!

I Hope this information will be useful to you.

if you need additional information,let us know to help you.

Thank you!!!:)

• Height and distance
• Sequence and series
• Sets
• Solving equations

• S and P block
• Surface chemistry
• Organic
• Physical all topics
• Atomic structure

• Dimensions
• Heat
• Flow of liquids
• Thermodynamics

hey Smriti

all topics will be cover by jee in exam .

as one topic is related with other and if talk about that topics which are the base of the subjects these are :

physics: kinematics; rotational;thermo;waves

maths: geometry; algebra; permutation and combination

chemistry : thermo; atomic structure; equilibrium;organic; s block etc.

but you should cover all the syllabus because your 12th will depend upon your 11th class concepts 

And in exam you can not depend on some of the topics ( if other topics came or you are unable to solve that question for which you know the concepts)

so better to prepare well and good.

good luck