As per the official website of Indian Navy, the eligibility conditions for the INDIAN NAVY is provided below:

Candidates on completion of the 10+2 (PCM) Examination or while in the 12th standard are eligible to compete. Successful candidates join the NDA or Naval Academy as Naval cadets. Combined Defence Services Examination (CDSE). University graduates are eligible to appear in the examination.

For the official website, visit the link below:

https://www.joinindiannavy.gov.in/en/faq/faq/index/officer#:~:text=Candidates%20on%20completion%20of%20the,to%20appear%20in%20the%20examination.

To know more about CDS Examination, visit the link below:

https://competition.careers360.com/exams/cds

I hope this answer helps. All the very best for your future endeavors!