USA

Most of the good universities will not accept, but if you choose tier 2 universities, then they may accept it. But, first you should choose some tier 2 universities in USA and email them and also your distance must be accredited by AICTE, IGNOU or UGC.

No, it is not necessary. But, if you have work experience, it will give you enhance your profile.

You must go for USA.

Hello,
Applications for Spring 2018 will be available from March 2017. Australia and NZ have intakes mainly in Feb and July. So the applications will be available from February 2017 itself. Whereas, for US universities you can apply in April 2017 for Spring 2018 intake.
All the best.

Hello,
Please find the link of top universities: https://www.timeshighereducation.com/world-university-rankings/2016/world-ranking#!/page/0/length/25/country/0/sort_by/rank_label/sort_order/asc

I wouldn't suggest you any of these because the living expenses in these countries is just of the league. In my opinion, go for Germany or New Zealand. Germany offers international students scholarships that result to very less fees or even no fees.
New Zealand is also offering many scholarships. The living expenses is quite low in these countries as compared to those countries which you have mentioned.
I hope it helps.

Your score must be 85-95% in boards for top ranking colleges like, Harvard and Stanford University and also for scholarship.

The higher score the better. 60% is the minimum recommended percentage.