Maths Spl

Hi Shivam, quite an ambiguous query, you have to know your interests and career plans and decide accordingly. Arts is a wide branch, mention the subject for suggestions of some sort.

Eligibility criteria to seek admission in Ph.D degree in mathematics is minimum. B.Tech candidates from any engineering discipline are also eligible to seek admission in Ph.D.
You are not eligible for seeking admission in Ph.D in mathematics with B.Com or M.Com degrees. PG Diploma is not to M.Sc mathematics, therefore, after PG Diploma in mathematics, you will not be eligible for seeking admission in Ph.D.

They won't entertain your percentage. At least, 70% is required to study in Canada.

It is a widely preferred group in 12th. The most preferred stream for PCM students is engineering. So if you want you can go for that.
In engineering, you can easily get jobs in IT firms. If you don't want in IT firms, then you must choose some core subjects like mechanical, EEE as they will give you a job in core companies which does not involve IT.

You are eligible to apply for BBA in all the universities. You will not face any problem in BBA studies because of your science background. In fact, your science background and better numerical ability and Data interpretation skills will help you crack BBA entrance examinations if you have good communication skills in the English language.

No you need to apply for JEE Mains and then advance and get good rank and on the basis of 12th class you can get a seat in IIT.

The following are some of the good universities for statistics in India:
1)Indian Statistical Institute (ISI), Kolkata
2)St. Stephen's College
3)St. Xavier's College, Mumbai
4)St. Xavier's College, Kolkata
5)Hansraj College
6)Hindu College
7)Ramjas College
(Delhi, Delhi, India)
8)Kirori Mal College
(Delhi, Delhi, India)
9)Indian Institute of Technology, BHU, Varanasi
(Varanasi, Uttar Pradesh, India)
10) Indian School of Mines (ISM)
(Dhanbad, Jharkhand, India)
11) Miranda House
(Delhi, Delhi, India)