Hello,
Categories don’t have separate page you just have to add categories from Product >> Categories and the page automatically created and it inherits the shop page layout by default.
If you want to display your categories in menu then go to Appearance >> Menus and add the Product Categories one by one.
Also your standard category page looks just fine you can check the below link:
http://n-el.ru.xsph.ru/product-category/clocks/
Best Regards.