A page of products in the app is called a Category. You can change the category a product appears in by going to the Categories setting of a product.
To include this product on an existing category page, click the down arrow. This will show you all the category pages already in the app.
Check the box next to the category you wish to add a product to. Click the down arrows to expand categories and sub-categories.
When you have selected your categories, click Done.
To remove a product from a category page, click the x next to the category name.
If you want to add a new category page to the app, click the New Category button. You can read more about adding new categories in ‘Categories‘.