i want to do b. tech in electronics... 

Well considering the fact that you want to take admission only on the basis of +2 exam marks reduces chance to get enrolled in good colleges since most of them have a requirement of JEE MAINS. But still you can apply in many govt. Colleges. For that every state has it's own counselling for the admission in the colleges. You can easily register for that and choose out for the college in which you want to take the admission. Once you have submitted the form, list will be released on the basis of marks and if you get the name in that list you can occupy your seat.
And as per the freedom higher category, the freedom fighrer should be in direct relation of your not someone like uncle or your grandfather brother. If the freedom fighrer is in direct relation with you, you will be given priority above all other who want the seat in ex-serviceman quota.