Whenever you want to add search, cart, wishlist and account icons in your site header, first, you need to click on edit button like below image.
After clicking button, edit header section will open. Here you can set widgetised sidebars in header content area in the edit header section using available header shortcodes like below image.
Now, you need to Go Admin > Appearance > Widgets and add search, cart, wishlist and account widgets in appropriate sidebar area. See below image for more understanding.
