Air carrier First Officer reported an unstabilized approach while circling for a visual approach at night; which resulted in a GPWS warning. The Captain performed a go around and returned for a landing.

Narrative

Aircraft X. Day 0 ZZZ-EWR Stadium visual 29 at night. Myself the First officer was Pilot Monitoring on the flight and on the approach into EWR. Everything was normal until about the last 1000' during the right descending turn into the runway. Around 1200' I the Pilot Monitoring had the runway end lights insight and called it out for my Captain (PF). He stated he had what I was seeing insight. As we came around in the turn it was very easy at this point to see the runway and I stated; Now I can see down range meaning we were almost lined up". As we got closer I called that we were overshooting and before we knew it; we received a GPWS terrain warning and executed the go around on RWY 29. After the go around we executed the approach again and this time stable and successful. Cause: PF Captain mistakenly miss interpreted lights on the airport thinking it was RWY 29 causing the airplane to be slightly low and left of runway centerline below 500' AGL Suggestions: Never accept an unfamiliar visual at night. Especially one that involves circling maneuvers."