No. Samaung Galaxy J5 Prime 3GB variant do not have front camera flash.
No. Samsung Galaxy J5 Prime 3GB RAM is not waterproof.
Yes, Galaxy J5 Prime is a VoLTE mobile phone.
Yes, you can use memory card in this phone and maximum capacity is 256GB.
No. Samsung Galaxy J5 Prime has 2 dedicated sim card slots and one dedicated memory card slot.