CBSE 12th

Well, there are so many career options as she is in 12th. First Do score good in 12th. She can appear for NEET through which she can get best college for MBBS. Pursuing MBBS from any private college will be very costly about more than 50 Lac rupees. Otherwise there some good courses like BPT (Physiotherapy), BDS B.Pharma and B.Sc. She can also go for one of them. One of these course she can get with less fee. Thanks.

You didn't satisfy the minimum board's criteria to get admission to NITs. Unfortunately, you can't get admission.

If you have completed your class 12th Science, then there is no procedure to change your subject to commerce. You can directly pursue BBA B.Com (Hons) or any such type of Commerce field.

See, first, do complete your graduation with B.Tech in any field you are interested in. After that, you have to appear for the entrance exams GRE or TOEFL, or IELTS for foreign universities. According to the score in these exams, you can get the admission in aboard for MS course. You can also get scholarship if you scores good. Your B.Tech results will also impact to get admission abroad. Hope this helps you.
Thanks.

See, you should not go for the diploma or engineering because you have less marks in 12th which will impact bad on your placements. Because almost all companies allow only those students to sit in interview who had minimum 55% marks in 10th and 12th both.
So, you should try for other course.
Thanks

No, only students who had PCB in 12th class can go for GNM course. You are not eligible for that.
You should go for other courses like B.Tech, B.Sc, B.C.A, B.Des, etc.
Thanks

You should go for B.Tech or BCA course and you can select the field in which you are interested like Mobile technology. You can do your B.Tech in same field. Thanks.

See, if you have maths, then some options are like B.Tech, B.Sc, BCA, B.Des and many more. According to me, you should either go for B.Tech or BCA. If you are from Bio, then you have options like MBBS, BPT, B.Pharma, B.Sc, etc.
Thanks.

Yes you can apply For BCA .fees is different as per college or university.Normally regular BCA fees is 30000 per semester and hostel fee normally 3500 to 5500 except security deposits.hostel fee may very as per college rules and regulations.

If you had not chosen Geography in the course applied for section, then you will do not get admission in this course.