Full stack invoice app using HMTL, CSS, JS, Node/Express and EJS

I am unsure how to allow the form to post more than one 'item' to the database, I think I need to change how the data is modeled to allow for this.

As mongo auto-generates the ID, I was unable to meet the ID spec, I believe there is a way to generate your own ID but I don't know how to do this.

I will research the above and also add filter/dark mode functionality and make it responsive.

Any feedback in the meantime is appreciated :)