Method – step-by-step:
1. In the WordPress backend dashboard – Go to: → Appearance → Menus;
2. If you don’t want a page showing all the products – Remove ?Shop? from Menu;
3. To add shop pages that will only show products in specific categories – At the top of your Menus window, click on ?Screen Options?;
4. Add a checkmark on ?Product Categories?;
Now you can simply add the ?Product Categories? to your menu;