Class 11

No, there will be no problem.
Do not think much and focus on your studies.
Live in present rather than in future.
JEE Mains is not a tough exam as many people think.
You can easily score 150+ marks.

Why do you want to go abroad? In India, there are many good colleges whose degrees are valid all over the world, so don't worry. As you are in class 11th, study well and try to go with IIT so that you get a valuable job easily.
All the best.

There is no prediction which question is asked from which topics. You can only analyze the last few years question papers and find out the most important topics and tips.
JEE Advanced physics most important topic:
Mechanics
Electrodynamics
Modern Physics
Optics
Heat & Thermodynamics
SHM & Waves
Mathematics:
Matrix & Determinants
Coordinate Geometry
Derivatives, Differential
Integral Calculus
Trigonometry
Complex Numbers
Quadratic Equation

Hi Nagasaiakash,
After 12th, your options include biotechnology, bioinformatics, forensic science, genetics, CABM, etc.

Hello Rahul,
Take your SAT or ACT and ace the exam. The application procedure is through the common app portal. Please note the university in question is one of the top most in the world and only scores won't be enough. Browse though the website and prepare. Take a look here:
https://college.harvard.edu/admissions/apply

I will prefer you to try TMH for scoring good in maths.
But the main thing is to go through previous year JEE questions which will give you an idea and many of the questions will clear your misconceptions.
GOOD LUCK

Together With books are good for practice purpose.
Best of luck.

It would be little difficult because you need speed for the JEE examination and for that you need to learn short cuts and various tricks, even if you want to self-study, then enroll for mock test papers and online tutorials of some good coaching institute.

Hi,
He can study abroad but the answer will depend on what he wants to study, his academic grades that is how much he scored in his 10+2, where he wants to study etc.Also he completed his 12th 2 years back so he has to show the cause or nature of the gap.