Nikon D810 Parts

whats the name of this part on nikon d810?
this part broke on my camera (
how can i fix this ?

Welcome aboard. Enjoy the ride.
We look forward to seeing more posts and samples of your work.

Wow, this looks like a major repair as you managed to break the main body structure. With an impact that significant, I would have to wonder what else might be damaged. I would definitively recommend a trip to the camera doctor.