To be honest with you, to complete 2 years of syllabus in 1 or 2 months is difficult. But what you can do is go by the weightage of each topic and then Categoriese the topics you are good at the topics you need to improve. Differentiate between 11th and 12th syllabus first. Then check if any topic from 11th is related to a topic in the 12th. If yes, they both should be studied together. That way you practise 2 topics at the same time. This saves time for you because you do have very less time on hand. In Physics, Modern Physics take the top slot with 5 questions. Heat and Thermodynamics, Optics, Current Electricity, Elcetrostatics get 3 questions each. Magnetic has 2 questions and the rest get 1 question each. In Chemistry, Transition Elements and Coordination Chemistry, Periodic Table and Representative elements take 3 questions slot. Thermodynamics and Gaseous state, Atomic structure, Chemical Bonding, Chemical and Iconic Equilibrium, Solid State and Surface Chemistry and Nuclear Chemistry and Environment get 2 questions slot eacch and the remaining get 1 question each.In Mathematics, Co-ordinate Geometry gets 5 questions. Limits, Continuity and Differentiability, Integral Calculus get 3 questions slot each. The rest get 2 and 1 questions slot. Practise as many sample papers as you can and atleast one mock test a week should be good practise. Now we also have Knockout package for your preparation: https://learn.careers360.com/engineering/jee-main/ . And few points to remember are:

You need to be physically fit to be prepared for what is ahead of you.

Keep telling yourself that you can. That is important

Make sure you improve on the speed in solving sample papers and quizzes

Take online mock tests

Focus on acuracy and speed as well

Improve your concepts and focus on weaker areas

Short breaks between change of subjects is really important

Do not overstress yourself

Avoid oversleeping during the day but get adequate sleep

Dont get nervous.