Hello,
The default WooCommerce provides the option to filter product only by an attribute. There is no option to filter by a category that is why you get to the category page.
Yes, you can create a page and display any type of products by means of product grid, however, please note, filters would not work on such page. They will work only on shop or category page.
As for promo banner you have not attached a screen. Please make sure that you have added content and images to your promo banner. You can send me your site admin, I will check.
Best Regards