Hii,

Yes a girl can join the navy provided if she has taken PCM at 10+2 level - and Maths/ Physics at

B. Sc. level.

So you already fulfilling the criteria so yes you can join.

You will have to appear for graduate entry CDSE exam conducted by UPSC.

For more information about this please visit the below mentioned link

https://www.careers360.com/question-i-am-just-doing-my-degree-bsc-physicsafter-completing-this-how-can-i-join-in-indian-airforce-or-indian-navy-in-officer-rank

Hope this will help you,

All the very best!!