Hii aspirant
For pursuing engineering you have to clear 10+2 with
Physics Chemistry and maths
And like you are not able to clear chemistry exam you will not be eligible
Forget computer science you are not even eligible for engineering in any stream
One thing you can do is to clear your compartment and prepare for JEE mains and other State level tests for Engineering along with VITEEE MUOET BITSAT
also or you can
Pursue polytechnic in computer science on 10th basis and get admissions through lateral entry process directly in 2nd year of engineering

I am sorry to say but you can't for Engineering (any branch) you need to clear your higher secondary class that is your 12th board class with any recognised board strictly in PCM. So first clear your 12th and then apply for Engineering.

Hi,
     No, you can't. You already registered yourself in Chemistry with your board. So, if you fail, there is no chance rather than passing chemistry in 12th, you can't change your subject at this stage. Only way to possible that you take re-admission in 11th.

Hello,
You can go for higher studies if and only if you clear your intermediate.
So firstly you have to clear all your papers.
Then you can take an entrance exam like JEE mains and get qualified with decent marks.
Then you can go for admission in computer science branch in Btech.
You have one year time.. prepare yourself that you will clear it in one time. Give your best. Study hard,do repeated revisions and practice problems.
Visit our career360 guidelines for preparation of JEE mains and advance.
Hope it helped!