Follow this post to install the latest version of android on your 4 year old motorola moto-g. The post has the link for rom and gapps.
- RIL (Calls, SMS, Data)
- Video Recording
- Video Playback
- Audio ( Record and Playback )
- Camera (Take pictures.(use the app mentioned above)
The latest android Oreo performs really great on the motorola moto G despite being a 4 year old device. The performance is excellent considering
Link for the dev, the ROM was developed by this Dev. Make sure to check his work as well.
If you have any doubts, do leave your comment on the video