No. Vivo Y83 does not have the particular LED flash for the front camera but it does have the display screen flash for the front camera.
Vivo Y83 has PowerVR GE8320 GPU.
No. Vivo Y83 is not a water-proof mobile phone.
There is no official announcement from the company if Vivo Y83 will support 5G network in future or not. But looking at the technical side of the phone specifications, we think that Vivo Y83 will support 5G network in future.