As Mire in Misery resolves, first the next opponent in turn order (or, if it’s an opponent’s turn, the opponent whose turn it is) chooses a creature or an enchantment they control, then each other opponent in turn order does the same, knowing the choices made before them. Then all the chosen permanents are sacrificed at the same time.

Your opponents choose what to sacrifice from among the creatures and enchantments they control. This means that you don’t decide which type of permanent a player sacrifices, and a player can’t choose to sacrifice an enchantment if they control none.