Thanks for posting. First reminder is that you are part of a large applicant pool-- Indian engineering applicants, and your GMAT is below the average of that group. However your academics appear strong, and some aspects of your work experience stand out, such as your projects in Spain and the US, which means you have experience working with those from international and different backgrounds and perspectives, which is also important at b-school and in your future career. The Teach India experience also stands out and sounds as though it was an important part of your daily life, so if you are able to speak to that and your rationale of getting involved in that, it would establish more about you than just a technical resume would.
Schools will also likely be interested to know why you have chosen consulting, and how you see your career progressing in the shorter and longer term.
In terms of the schools you've listed, ISB and NUS will be a bit of a reach, though not impossible; and Oxford/Cambridge likely as well. You may have a slightly better shot at the others on your list, though all require compelling essays, application, & interview for a chance at success. Keep in mind the NUMBER of schools you apply to.... each application is quite involved and time-consuming, so most applicants apply to 3-4 schools, or if spread over several rounds, maybe 4-6.
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. And/or feel free to check back in here! Good luck!
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