Greetings!

Do not worry about changing the board from State to CBSE as most of the time there are many of the students do the same every year. So that is absolutely not a big deal and can be done so. But there will be a lot of procedures that you will have to go through and it might be troublesome for you and your family. Also it might take a lot of time and you might as well get admission in the school having CBSE but at very later stages and you might lose on the classes that the students of your class have taken and you might lag behind in your curriculum. You will then have to rush up with the syllabus to score good marks. Also, not all CBSE school will accept that case, you this may cause you a lot trouble. They have their own norms that they follow in this area which no one interrupts. Most of the schools have fears about their class 12th result because of which they do not entertain new admissions in class 12th at one go. So you will also have to look for a school that is willing to take you. If you already have contacts in school that can take you the surely go about it and do try once if you have the urge to try and get good marks in your class 12th examinations. As far as good colleges are concerned it does not matter to them if you have done your 12th twice as well they are concerned just with a good score in your 12th class. Especially colleges like Delhi University take admissions in may courses purely on the basis of the merit list that they prepare so you need not worry about it.

I hope this was helpful. Thank you!