Air carrier Captain reported a CFIT event during final approach that was caused by the First Officer deviating below glide path. The First Officer took correct action and landed safely.

Narrative

I'm the Captain operating Aircraft X from ZZZ1 to ZZZ. I'm a relatively new Captain; only about 35 hours post IOE. My (FO) First Officer was around a year's experience; +/- a couple hundred hours in the airplane. It was his leg; and all was fine until the final descent into ZZZ. Weather was not a factor; as it was relatively clear. On the downwind portion; to the visual X; ATC gave an early turn to final; still around 4000 ft.; inside of ZZZZZ. I didn't want to begin stepping on my FO's toes; so I waited for him to start announcing instructions to help intercept and descend for the approach. As the FO focused on descending onto the path; he realized the non VNAV equipped aircraft would not auto switch to the approach; so his lack of guidance distracted him; and I told him to hand fly if it became necessary; rather than wait for the automation. He disconnected the Autopilot. He still didn't flip over to the green needles; but; as it was a visual approach; I ignored it; hoping he would focus on the now visible PAPI indicators ahead. I became distracted with configuring the aircraft and noticed just outside the bridge that the PAPIs were nearly all red. I announced the condition; and he corrected; but likely not with enough thrust. As we were over the river; there was no significant terrain except the visible water; so I allowed the approach to continue. He crossed over the approach light system as the aural 50 ft. call sounded. We still landed on the thousand foot markers; and exited the runway safely. It was only after we parked at the gate that it became clear to me the FO was more than just unhappy with the approach. There was mention of items that suggested fatigue; as he had not had anything to eat; and had been continually on the go since this morning; before our first flight together.