Add a category
Open Menu Library → Categories and tap +.

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Name it — at least two characters. This is what customers see on the kiosk and online, and what staff see on the POS.

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Use Assign to pages to tick which menus it appears on — the POS menu, any Kiosk & Online page, or several at once.

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Pick an image if you want one. Without it the category shows a placeholder.

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Add products with Add product. To set the order customers see them in, tap Edit Order and drag them.

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Tap Add. On a category that already exists, the same button reads Save.

Kitchen printer settings
This section only appears once you have a kitchen printer configured.

- Print on Kitchen Ticket — off means this category never prints, whatever else is set.
- Print Small at End — groups the category compactly at the bottom of the ticket. For extras — sauces or napkins, for example — rather than for a course.
- Kitchen Ticket Order — lower prints first. Number your categories so the ticket flows the way the kitchen fires — for example, cold first, then hot, then desserts.
- Select Printers — appears once you have two or more. A category with none selected prints on every kitchen printer, which is the safe default.
Add a product
Open Menu Library → Products and tap +.

Name, description, price, then attach any choice groups or options it needs. Save, then add it to a category.
You can do the same from the POS under Menubook.
Hiding and deleting
Every category and product has an Enabled toggle. Turning it off disables the item — it stops appearing on ordering screens, and everything else about it is kept. That's the sensible move for a seasonal item. You also choose for how long: Disable for today in Back Office (For today on the POS) brings it back at 4 a.m. the next day, and Disable indefinitely (Indefinitely) keeps it off until you turn it back on.

To keep a product on the POS but off some of your customer channels, see Hiding a product from a sales channel.
Deleting is different and permanent. Your reports are fine either way, since past sales keep their own record of the name and price. But a deleted product is stripped out of every category and menu it was on, so bringing it back means building it again. Deleting a category leaves its products alone — they stay in the Library, just unassigned.