Zelda II is weird. There is no way to select items to use, but instead, items are equipped and used automatically, and spells are used to change up how you play. As for the child...yeah it's hilarious. You fall down some random hole and lookie there a child sitting in a cave. I thought it was a doll until I took it to a lady and she said "You found my son!"
Also, CHILD!? What?