B.Sc Physics

You can refer to the following link to get an idea of DU cut-off 2018:
http://www.du.ac.in/du/index.php?page=cut-off-2017
Hope this helps.

Yes you can try for scholarship as well.that may reduse your study fee.and also you may get stipend too.

Their eligibility criteria is should pass 12th from any recognized board in Science (PCM) with 70% marks.
If you are in the category OBC-A/OBC-B, you need only 65% marks.
If you are in SC/ST/PD/sports category, you need only 52.5% marks.

To receive admission in M.Sc Physics course, candidates must have had graduation degree in specified specialisation (physics). For the courses having entrance examination and interview, the admission to the course will be through an entrance test, which results in the shortlisting of the candidates for the interview. 50% seats shall be filled by direct admission of the students of the University of Delhi only, on the basis of merit. This mode is not available to students from other universities. Remaining 50% of the seats shall be filled through entrance examination and Interview/Group Discussion if any.

Please check for admission details regarding this course at college website.
(Website:- http://www.stellamariscollege.org)
Alternatively, download college brochure from the link mentioned below, for details regarding admissions and eligibility to this course.
https://www.shiksha.com/medicine-health-sciences/paramedical/course/pg-diploma-in-medical-laboratory-technology-stella-maris-college-cathedral-road-chennai-86065

Please check for your eligibility to pursue Post Graduate Diploma in Perfusion Technology at Apollo Institute of Hospital Management and Allied Sciences from the criteria mentioned at the link provided below:
https://www.shiksha.com/medicine-health-sciences/paramedical/course/post-graduate-diploma-in-perfusion-technology-apollo-institute-of-hospital-management-and-allied-sciences-ayanambakkam-chennai-175707

No, it's quite different. Everything is different be it paper pattern, or studies or syllabus. It is an undergraduate programme and that is higher secondary exam. Moreover, level of toughness depends upon your college.

If you are very weak in English, start from beginning learning basics of English. Basic Rules and Grammar of English. If you are aware of these things then it's good, then start watching English movies, shows, etc. It will create an environment for you. Start English conversations with your friends and family if they are supportive. Try speaking English in front of mirror, try speaking on the different essay, speech topics. Try writing essays and speeches in English. This will help you in improving your English.