hi its me the creator of Usefull Commands in a Spawnegg i have updated it with more features such as
TimeNight that allows you to set the time to night
SpawnArmorStand this spawns an ArmorStand
SetSpawnpoint that sets spawnpoints
KeepInvOn that turns Gamerule KeepInventory true
KeepInvOff that turns Gamerule KeepInventory false
NOTE signs may not be visible but they are there if you cant see them then just relog from your world/server or reload chunks