Yes, you can use it. But at any given time, one sim will work on 4G network and another will work in 3G network.
No. Micromax Bharat 4 does not have the hybrid sim slots. It has 2 dedicated sim slots and 1 dedicated MicroSD card slot.
Yes, Micromax Bharat 4 has a removable battery.
No. Micromax Bharat 4 does not have the gorilla glass protection but it does have the full lamination technology.
Yes, Micromax Bharat 4 is a VoLTE mobile phone.