Dear Ajay,
Congrats on performing so well in your high school.  But if you want admission in a good reputation college you need To clear JEE MAINS and To get into IIT you need To Clear JEE advance.  The rank you score  totally depends on how well you perform in the exams listed above.  However, you can also go for BITS,  VIT, PEC or PU.  VITS and BITS  conduct their separate entrance exam where PEC and PU are concerned with your rank in JEE mains. 
There are other several private institutes as well like Thapar, chitkara  etc. 
Have a great day.

for btech admission are on the basis of jee mains and advance and cet

for admission some college do 50%-50% in boards and in jee or cet

Hey Aspirant,

Yes You can Get Admission in Private Colleges directly. Like LPU,GU,CU. But if you wish for IIT,NIT, IIITs or GFTIs then you must appear in JEE-MAINS or you should appear State Entrance Exam and qualify them with good marks to get into government engineering colleges. 

Best of luck

Dear aspirant, 

You can apply for direct admission in b.tech on 12th basis and according to your marks in class 12 you can also get IT branch even if you are a uttar pradesh domicile then you can apply in top private colleges of Aktu and can get computer science branch also. 

what is your JEE Mains Score ?