From your Shopify admin, go to Online Store > Themes.
Click the
...
beside the theme that you want to edit.Select Edit default theme content from the dropdown menu.
Click the tab or category that includes the text that you want to change (Checkout & System), or use the Filter items search bar to locate phrases or words you want to change.
Click the
...
on the right to reveal hidden tabs or categories:Edit the text.
Click Save
This option is particularly useful for merchants wanting to change the text of the optional address line which has the default text 'Apartment, suite, etc.'
Standard default text for Delivery / Shipping form
Customised text for Delivery / Shipping form
Reference for standard address form field labels and placeholder texts