i have managed to add the note for the product when checking out the product. I need to update the note in the code depending on some price conditions from the prodcuts
like if the price is less then 100 i need to place a special note in the note . i prefer to append to the note in case the user has entered a note
It's possible for you to implement but only if you know JS
On keypress in note 'textarea' check the price of product. You can get product by ID/class use one which you preferred.
Once you get it in JS write down a condition
if product price is les than 100 then append your specific text.
You can find both 'keypress' and 'append' function on google.