What are some online courses available on Coursera which will help us get into Ivy League universities like Harvard or Stanford?

Go to each target college’s admissions site to see which courses and prerequisites they recommend for applicants.

Take whichever courses on a site like Coursera will prepare you as far into your majors of interest as possible. At the very least, try getting a perfect score on each standardized test you intend upon submitting for your college. Perfect SATs, perfect SAT 2s, perfect APs, perfect IBs, and so on.

After you have come as close to acing all of these exams as possible (maybe with the help of Coursera), try taking higher level classes at each target school if you can find them in Coursera.