/kill @e " armor stand " die together with players

Armor stands are entities.

Players are enemies too,so If you want to kill armor stands(they are also entity):
./kill @e[type=minecraft:armor_stand] that's the right command.
If you want to kill something else,try to change "minecraft:armor_stand"
If you want to kill everything else but you, "type=!minecraft:player"

Have a good day.