Those buttons are not category buttons, they are custom product buttons setup for a retail type environment when you enter a price on the keypad and the select one of those buttons
So you would key in 5.00 and press the grocery button and it would add grocery as a product on the ticket with price 5.00
If you want category buttons across the screen like that you would need to make a menu screen using custom products, you can only have categories in a column as default
Those custom buttons would then open another menu when pressed, showing the products associated to it
I’ve created a retail type setup that doesn’t use the built in category system at all, I use multiple menus and all the buttons on my screen are custom product buttons that either add a product to the ticket or open another menu with other products or options
Have a look at my tutorials these two are two different ways I have used, I now use tutorial 14 in my retail and bar setup as it’s easier to change and amend than the code part in tutorial 15