if a land is a monster and a land does it die

[NIKTER]

if a land is both a monster and a land does it die

[DatAsh]

Why would it? Why would they make lands that become creatures if they'd just die right away? Unless you mean CAN it die? Then the answer is yes, it CAN. It doesn't matter what other types it has, if it's a creature, it's a creature. If it's a Land Creature, it's a Land and a Creature.