LWC is an auto-locking plugin that provides protection to your chests/furnaces/etc to prevent unauthorized access to your items.
Chests/Furnaces/etc are auto-lockable in Survival/Creative/Skyblock gamemodes by simply placing down it. For example:
To lock a Chest/Furnace/etc, simply run /lock and right-click on the block you want to apply lock to:
To unlock a Chest/Furnace/etc you own, simply run /unlock and right-click on the block you want to remove the lock from:
To turn your Chest/Furnace/etc to a public-lock for others to access without destroying your block, simply run /cpublic and right-click on block to apply the change to:
To give someone access to your Chest/Furnace/etc, simply run /cmodify <player> and right-click on block to apply the change to. For example, if I want to give ilovethem access to my chest, I simply do /cmodify ilovethem and right-click on my chest. Here's a pic to show what it'll look like:
If I want to remove ilovethem from my chest I simply add minus symbol (-) to the left of the player's name: /cmodify -ilovethem and right-click on chest to apply the change. Here's a pic of what it'll look like: