Hello,
even you join they will post all the openings. They do every year. you have to apply for it if you are eligible and go through the process to get selected. There are like list of eligibility criteria and requirements to join navy or army so you have to fullfill it. If you do then you will join after qualifying the exams and screening tests.
Keep on checking the official webpage for regular posts. They will post anytime as they want and you will miss the date. ask your friends to help you too if they are interested too.
Hope it helps!
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