Limit one item from category per customer in Cart page (WITHOUT APPS)

[Elia18]

Hello everybody,

I'm looking to solve a problem, I need to limit one item (from a collection) per customer per purchase.

I saw that with the new features from Shopify Editions Winter '23, we could do things with the code, and I'm sending the screenshot that proves that shopify now allows us to Limit one item(from collection) per Purchase, even they shared some code, but I'm not sure if is it correct and where I can put that.

If anyone has a clue, it will be a fantastic help! here you have the screenshot and the video:

Anybody knows if this code is correct and where we can put that?

Thanks in advance 😄