Yes! You can add notes to the order or individual line items.
To add a note to the kiosk order, make sure the Order Kiosk setting for "Collect Customer Information" is selected and not skipped to place an order. This will prompt the customer to place an order note when the order is ready to be placed.
To allow customers to add notes to individual line items, create a Label called Kiosk Note. You will need to explicitly add this verbiage to the new Label for this feature to work. Apply that label to all items you would like customers to be able to add notes to. When a customer adds those items to their order, the customer will be prompted with an option to add a note to that item!