CBSE 10th

Visit this link
https://www.shiksha.com/colleges/mba-colleges

No, you should go after class 12th.

It is better if you chose any of the streams like Science, arts or commerce.

Yes, you can get admission. All the best.

Hi,
Visit this link for more information:
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor.
Thank you.

Hi,
Visit this link for more information:
https://www.shiksha.com/b-tech/resources/jee-mains-college-predictor.
Thank you.

Your academic performance up to class 12th is excellent and hope for a much better performance for B.Com also. The last year's IIM-Lucknow cut-off for CAT is given below for an idea and for future preparation for the General candidate.
For the PGP program the sectional cut-off was 85 percentile for V

Yes, you are eligible for this college also specify what course you want to pursue. Thanks.

I think, it is better to pursue CAT mainly, because if you do CAT you will get admission to the best IIM in the country like IIM-Ahmedabad, Bangalore and Calcutta. If you are really interested in management, then these are really good institutes and you should aim for these institutes.