on join:
set slot 9 of player to stick named "stick" with lore "stick", "stick", and "stick"
# this is if you dont want the player to be able to move or drop the item
on inventory click:
event-inventory = player's inventory
index of event-slot is 9
cancel event
on drop:
if event-item is stick named "stick" with lore "stick", "stick", and "stick":
cancel event
send "You cannot drop this"
not tested so idk if it will 100% work but it has no errors. There may still be other ways the player may be able to move the item such as off hand switch but just cancel that or any other event too.