How can I study BSc in the USA after completing 12th from India? 

If you have completed 12th grade in India and want to study for a Bachelor of Science (BSc) degree in the USA, here are the general steps you should follow:

1. Research universities and programs: Research universities and programs that offer BSc degrees in your field of interest. You can find this information on university websites or by using online resources, such as the College Board's College Search tool or Peterson's Guide or your preferred study abroad consultancy’s website or app.
2. Meet admission requirements: Review the admission requirements for each university and program you are interested in. Generally, you will need to take the SAT or ACT exams and demonstrate English language proficiency by taking exams such as the TOEFL or IELTS.
3. Apply to universities: Once you have identified the universities and programs you are interested in, you can begin the application process. This typically involves submitting transcripts, test scores, essays, and other materials, as well as paying application fees.
4. Apply for financial aid: If you need financial assistance to pay for your education, you should apply for financial aid by submitting the Free Application for Federal Student Aid (FAFSA) and/or any additional forms required by your university.
5. Obtain a student visa: If you are accepted to a university in the USA, you will need to obtain a student visa. The type of visa you need will depend on the length of your program and other factors.

You may want to consider working with a study abroad consultant, who can help guide you through the application process.