Bachelors

LA Trobe University
UTS, University of Technology, Sydney
University of Wollongong
University of Southern Queensland
Curtin University
Swinburne University of Technology
UTAS (University of Tansamia)

For mass communication, both are good, bachelor's as well as Master's. But, it's preferable that you must complete your Bachelors from India and then you can continue your studies I.e. Master abroad.

Yes, you can retake admission for your UG course. The admission will be based on a personal interview wherein your aptitude for the course will be determined. And you can't say that the college is best for this course, but a fine one.

Yes, of course, you can. You need to clear English proficiency test i.e. IELTS for that and the required band set by the particular university in which you are interested.

Refer this link for admission process of IGNOU : https://www.shiksha.com/university/ignou-indira-gandhi-national-open-university-delhi-3030/admission.

Please specify the college/institute name.

No, they do not offer a sport Science course.

The requirements are same as for international students irrespective of the nationality. Take SAT or ACT to apply to undergraduate course. For Masters you must take GRE and for MBA GMAT is accepted. Keep in mind that the specific requirements differ from university to university, you have to visit university websites to check out the requirements before you apply. In addition to the above, you must have good grades.

Yes, if you want to do B.A. BCA B.A. So, you can apply for DU JAT (Joint Entrance Test) but this is not for B.Com.
Good luck!