Your POS is the source of all information. Therefore, if you want to offer products with options online, first create them in your Lightspeed Restaurant (K-Series) POS. Created products can then be synced to Deliverect.
To learn how to manage your items, view this article on Lightspeed's help center.
Sync your products to show the newly created items in Deliverect. They can then be used in your menus.