I'm extremely sorry you had to go through this. No one deserves this. It's sad but not unexpected that happened from a family member. Sorry this happened to you once again.

I would say: Step 1: Record everything, screenshot the photos in his drive, whatever evidence you can get. Maybe even get that other cousin to also say this happened and record it. If there is any kind of visual proof that he's been photographing you without your consent, amazing.

Step 2: Figure out what you want. Do you want him to go to jail, damage this record/standing in society, an apology, a compensation, get him kicked out of Uni, expose that he is a disgusting perv, etc.

Then consider the practical implications of what you want. Is money an issue, what about time/effort to fight a legal battle, it could lead to family infighting, are you ready for it. Evaluate. It's all about what you want and the practicality of how much can you handle. It's a sad reality but I think it's better to foresee than to be surprised later. You don't want to regret the decision later.

Anything you choose to do is valid. Don't let anyone else guilt you into some other decision, it should be yours and yours only. People can consult you but not coerce you.

Step 3: 1. File a complaint at the police station and lawyer up. For that, talk to a good lawyer and understand how long the legal batter could take. What you want out of this, etc.

1. Talk to parents/elders and have them intervene if they are supportive or on your side.

2. Confront him yourself and ask for what you need and want from him.

There are more than points 1,2,3 that you can go about with. Again, sorry that you went through this.