Attach player to physics bones?

I’m testing some game play things for rope climbing in game and am following this tutorial ( for creating ropes using bones. I saw that someone in the comments asked the videos creator if you could attach a player to the rope so they could move up and down the bones.
This user in the comment thread was able to get this to work. They wrote “I managed to socket each constraint and I attach the player to each one and move him up and down the chain if he inputs W or S”. My question is how you attach a player to the ropes bones. I can’t find a way. The ‘socket each constraint’ part of his comment also eludes me.