Hi krishna..,
You can join short term coaching in the best colleges in your area.
So that you can improve your score

• Don't try to prepare for multi  exams..,
  
• Select an entrance which  you're capable to crack.,
  
• Focus on that  single exams and give other exams if you are interested, but you should primarily focus on the selected exam.
  
• Practice number of problems
  
• Check out previous papers and note the maximum scoring areas
  
• Divide the chapters based on your convinience, and their importance.,  and go through them.
  

Thank you

• For any other queries please do comment.
  

Now in this time choose those topics which are having most number .Prepare them as much as you can. And also prepare those topics which you like most of all three subject and solve previous years question and give mocktests as much as you can .

Dear Krishna, JEE Mains is the National Level Entrance Examination for admission into Engineering and Technology courses in NIITs, IIITs and CFTIs. Those who qualify in JEE Mains are eligible for JEE Advanved. Those who qualify in JEE Advanced can gain admission in IITs. So for at rhe National Level Engineering courses, JEE is the entrance examination. And there are State Level Entrance examinations as well. Many colleges take admission based on JEE mains score. So your next step should be to appear for JEE Mains. As you are hard working and willing to walk the extra mile, we are sure, you will make it.