CBSE 12th

It depends on your stream of class 12th.

Oh dear it is the time varying things many toppers also from in the south India in the past. another important thing you should check the marks of regional topper you will find the difference is of .5to 1% marks only. So it's a matter of luck nothing else. Don't think negative focus on your studies you may top.

Yes you can do B.A but not B.Ed. As for B.Ed. you should be a graduate however you can do D.Ed. it's diploma in Education and minimum eligibility for it is 12th pass. You can do it by Open University k Ike IGNOU

yes in Delhi University and in many other universities you will get admission in 12th marks too and in many colleges and universities take its own entrance test

Everything is possible in UP. You can get a good college for B.Tech through spot round.

for judicial service you require graduation with law background. you may go for bba LLB or BA LLB for your graduation. it will help to clear your eligibility criteria as well as subject knowledge too.

Dear, your question is not clear.

it is not a problem if you are a good developer. in industry they respect the talent more than the percentage of marks no don't worry focus on your work. All the best.