JEE Main

Hello Harshit,
Yes, it's good to join a crash course. They give training good level of questions and how to solve question paper and also, teach tricks in quick answering. Regards.

No, this is not the eligibility criteria to appear in JEE Mains.
It is for getting admission in NITs and IITs.

The only eligibility is that you must have Science in your 10+2 standard from any recognised board and must be a citizen of India.

The final AIR will be declared after April 2019, considering the best score out of the two JEE Main attempts for all the applicants, hence based on current percentile we cannot predict for which all colleges you are eligible. Wait for the final AIR declaration.
Details:
https://www.shiksha.com/b-tech/articles/how-to-calculate-jee-main-rank-from-percentile-blogId-19953.

You have good chances to get admission with this score. Keep trying hard, and in meantime do keep eye on other colleges too to have a safe hand.

Hi there,
Different colleges have different criteria for JEE. For Thapar Institute in Patiala, you can apply through two criterias. 1) Based on your JEE score and 2) Based on your 12th class percentage (PCM OR PCB). The division of seats for the above two is 30% and 70% respectively. You can choose as per your suiting. The institute has just opened this application form.

The final AIR will be declared after April 2019 considering the best score out of the two JEE Main attempts for all the applicants, hence based on current percentile we cannot predict which all colleges you can get. Wait for the final AIR declaration
Details:
https://www.shiksha.com/b-tech/articles/how-to-calculate-jee-main-rank-from-percentile-blogId-19953.

41 percentile is quite low to get admission in JNTU, you will not be able to secure admission with this.

Yes, you can qualify for advance.

Yes, definitely. There are a lot of solved question banks for NATA and JEE Paper 2 exams, that would be helpful for you, more than this the sketching ability improvement would be a great addition for these exams.