You can absolutely add this without issue, please check the following one so you can generate the required fields here: Line Item Property – Shopify UI Elements Generator (myshopify.com)
Thank you very much for your answer!
It should look like this and it should be able to edit the fields for each item. Is that what we can create with the provided link from you?
I was also searching for the section you have mentioned and didn't find where exactly to insert the code.
Thank you in advance