'Rear Camera' and 'Flash light' Not Working in Lenovo k6 Note (Custom Rom)
u need to flash the rom named Karatep. the one you flashed in for k6 power. 
K6 Power(Karate)
K6 Note (Karatep)

https://forum.xda-developers.com/k6-power/development/stable-unofficial-lineageos-lenovo-vibe-t3635064