Catalogs have to be maintained for maintaining inventories thease are used for grouping of similar inventory items. Follow bellow path to redirect to catalogs
Business Portal > Operation > Manage Menu > Catalog Overview
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In Manage Catalog you’ll see that there are some demo catalogs already in the list.(To remove a catalog, follow path as More > Remove
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and your catalog will be deleted from the list.)
Remove all existing catalogs to create new catalogs as per your business only
Now you can setup Catalog/Menu as per your requirement