CBSE 12th

If you understand all the named reactions and their process. You can score marks in Organic Chemistry.
It is so simple to memorize those named reaction, but you must also know for what they are used, if you know that you can master class 12th organic Chemistry.

Hi Vishwateja,
I would like to suggest you to follow the syllabus and last year's paper including sample papers. This things will help you a lot. Best of luck.

Both has equal weightage. No one can say that problems are asked more than theory and vice versa.

No, just question yourself this. If it was possible to do B.Com/B.Sc/BA in a year, then why would people choose to do it in 3 years? No one can do a graduation degree in a year, no matter what your qualification is. You can pursue a course from the second year if you have a Diploma in the related field. Even then, you would complete it in 2 years.

I think you should thoroughly practice the exercise questions as much as possible for chemistry and also the questions which are in mid of the chapters, it will definitely help you and for the chapter. Chemistry in everyday life, a thorough reading of complete chapter is mandatory as most of the questions are from mid of the para.

No, you can't pursue Master's degree directly after your PUC / 12th because there is no such way to do so, and you need to pursue a UG before pursuing a Master's degree course.

To repeat your class 12th, you need to write all the exams again so, take supplementary exams for all the 3 subjects.