Thanks for taking the time to open an assistance request!

How can I make an item unbreakable / or is it even possible?

Pastebin
Config.yml | https://pastebin.com/n11hTvR0
en-lang.yml | the original
items.yml | https://pastebin.com/zXrXUJBq
(if u need database.db also, write it me)

Please complete the following information:

• Resource Version and Build Number: idk?
• Server Version Paper 1.16.5

Additional context
No

I am unsure how this managed to slip by me but you can indeed make items unbreakable!
Simply add the unbreakable itemflag to the custom items you desire to be unbreakable.

Example
itemflags: unbreakable, self-drops, death-drops
or itemflags: unbreakable

You can also do this in-game via the /itemjoin menu

Please let me know if you need additional help!

EDIT: Marking as inactive, please reopen this issue if you still need additional help.