Help - Reverse connect battery

Last week driving and got engine light and say pull over and all dash light on no red triangle but or angle triangle with exclamation. Check code it say P2161B need replace water pump. I have new water pump. Also full dashboard light on. Say battery low I went bought new battery and connect but I connect reverse cbattery and . I lost radio on and no power dashboard on. Headlight on open door light no start. Replace fuse fusible link box and check terminal battery fuse still good. 120 fuse inside the fuse box good. Unable to read OBD but my friend has snap OBD reading P0A0D U0L00 U0129 U0164 everything lost communication. Try test under dash fuse all has no power. Door light on car light on head light on. Cant push start red light no green.