I am from India, and I regret greatly choosing humanities as my subject in the 12th grade. I don’t believe this industry offers any employment opportunities. Political science and history are disciplines I thought I loved, yet there are virtually no jobs I can get with them. It’s worse because I don’t feel especially passionate about anything yet. In addition, I no longer wish to reside in India. But I have no idea about applying to colleges abroad, and I haven’t even studied for any exams like the SAT or TOEFL.
Are you about to enter 12th grade, or have you already finished 12th grade?
What is the highest level of mathematics that you have completed? How have you done in your math classes?
What science classes have you taken, and how have you done in them?
In North America (both the US and Canada) it is relatively common for students to change their mind on their major even after starting university. Decades ago I attended a university that did not even allow me to choose a major until after completing my freshman year. Both daughters changed their major after their freshman year of university. This is quite common over here.
If you are going to want to go into a “STEM” field (ie, science, technology, engineering, or mathematics – note that computer science is included in this group), then you will need to have some background in mathematics and science. It is useful for example to at least be ready to take calculus when you arrive in university (ie, to have completed the prerequisites and done well in them). However, some students first graduate high school, and then take some earlier courses that will help them prepare for these fields. Again changing majors late happens.
At least here in North America there are students who go into technology at least as late as you are at, and in some cases somewhat later. It is definitely not too late at least over here. I am not as familiar with the education system in India but hopefully something similar is possible there.
Regarding the TOEFL, how is you English? Your post seems quite well written which is at least a hopeful sign. If your English is strong, then you just sign up for the exam and take it. It seems likely that some TOEFL preparation classes might be available to you but if your English is already strong you probably will not need all that much preparation. A small amount of preparation may help quite a bit.
Your budget for university will matter quite a bit. University in the US is typically very expensive. There are only a small number of universities which provide full financial aid for international students, and they tend to be very competitive for admissions. University in Canada is sort of in the middle in terms of expense – less expensive than the US but still not cheap, and full scholarships are very, very rare in Canada.
In terms of residing and working outside of India, that could be more difficult. Immigration to the US is complicated and very difficult. International students who graduate from university in the US are typically expected to return to their home country. Canada has a process to first get a degree there, then get a temporary work permit, and then if things work out apply with employer sponsorship for a permanent resident visa. However, just getting a job in Canada can be very difficult with your choice of major having some impact on how difficult.
I think that’s a bit of a hyperbole. There are plenty of non-STEM jobs out there. You need to figure out what works best for you. If you aren’t sure where your passions lie you may want to use a career guidance service (I just googled “career guidance India” and found a bunch of services) or speak to professors or professionals you know. Unfortunately it’s very hard for us who don’t know you or your interests to provide any meaningful guidance.
As @DadTwoGirls pointed out above, coming to the U.S. for your undergraduate studies is challenging for multiple reasons so I strongly recommend you first explore options in India.
English is spoken by a sizable chunk of the Indian population and if OP studied in a major city s/he likely had their entire education in English. But I want to point out that the TOEFL tests American English including being able to understand American colloquialisms. That’s something that often trips up non-native speakers and definitely requires some level of preparation. (Source: my wife used to be an ESL teacher and TOEFL grader).