No. Redmi Y2 is made of industrial grade polycarbonate material.
No. None of the Xiaomi phones comes with the earphone. You have to purchase it separately.
No. Redmi Y2 is not a waterproof mobile phone.
No. Redmi Y2 does not have the Gorilla Glass protection.
The Xiaomi Redmi Y2 is a slightly better attempt at a selfie-focused smartphone than the model it replaces. It has proven hardware that is capable of delivering a smooth user experience, plus MIUI 9.5 which has a lot of added features.