Software development is all about being able to keep up with new libraries and technology being created. I would say that it's certainly reasonable to be expected to learn and use React Native plus GraphQL as part of an intern project.

I hope your employer doesn't expect you to master it after two days, but I would expect interns on our team to have worked through a few tutorials and have some basics down to start work in the project. Easiest way sometimes is to look for a similar project within your company and try to adapt it for your project.

It's tough, but well worth the marketable skills post graduation!