add a JavaScript code Laravel based store

I have a store where I want users to add some info about his order. The form is complete, but I need someone to add a space where the user can draw freely. When the user submits their work, it should be saved to a database. I can then see it on the admin panel when their order is received. The custom work form is functional, I just need this specific addition.

Check attached GIF for more details:
https://i.imgur.com/ECft1ZX.gif