JEE Main Eligibility

Hello,
This exam is national level examination conducts to provide admissions in undergraduate engineering courses in IITs, NITs and IIITs. Your date of birth falls on or after 1st October, 1994 (for general and OBC candidate) are eligible to apply. You must qualify 10+2 or equivalent examination from a recognised board. You must have to take minimum 5 subjects in 12th/equivalent examination. Candidates appearing for JEE Main must have passed class 12th with physics and mathematics as compulsory subjects along with one of the chemistry/biotechnology/biology/ technical vocational subject.

No, you should try next time. You should have 3000 rank maximum to get admission in this college.

Yes, you are eligible for JEE Mains paper in the year 2019, because you can give exam 3 times in a row after completing class 12th. You won't be able to get a seat in IIT, because you don't have 75% marks, which is the criteria for JEE Advanced. (For IIT).

Uttar Pradesh. To get confirmation, apply for a residential certificate.

Yes, you can appear for the 3 subjects. Clear the requisite of 75% marks as said by JEE Mains.

You need to give the NATA exam (preferably before the end of May) and then in the month of June-July apply for the admission process of DTE. If your NATA score and 12th percentage are really good then you might get into Sir J.J. college of Architecturing.
Admission to B.Arch. is done on the basis of valid score obtained in NATA/ JEE Main 2018.

Yes, you are eligible for JEE Mains provided you have 75% in class 12th. It doesn't matter that you have appeared for any other examination or not.

Yes, you are eligible for both JEE Mains and Advance.

Surely you are eligible to give the exam. But you will be disqualified in the document verification round at the time when you report to the college. Hence you should not give JEE Mains.