This is the only thing I couldn't figure out. I've followed the video to set up the nodes for the wet part of the beach.
It reflects the HDR, but not the character at the center of the scene, only its shadow. What is it that is missing?
You may need to enable screen space reflections to enable reflection of non static objects, you may also need to add light probes
As shown in these screenshots i added a flattened cube reduced its roughness to 0, turned on screen space reflection and added a light probe for planes that surrounds the flat part and it creates a mirror like finish.
The screen space reflections weren't enabled. That solved the problem, thank you!