Editing Custom Text on Checkout Page (not part of form)

I apologize if this is elementary, but for the life of me I have not been able to figure this out. I have a wordpress website with a woocommerce store. On my checkout page, besides all the normal checkout form fields (name, address, etc), we have a textbox that says something like “if you’re ordering outside the US, call this phone number”. I need to edit this text, but I’m unsure how to do that.

Normally if I want to edit the text of a page, I go to WordPress dashboard> Pages>Page I want to edit>Edit> then there’s a textbox which has all the content of the page. However, when I do this for the Checkout page, the only text in the textbox is the “[woocommerce_checkout]” shortcode. There doesn’t seem to be an option to edit the actual content on the page. I understand that by going to WooCommerce>Checkout Form, I can edit the form fields, but I can’t find how to edit the page outside of the form. I also tried going to Appearance>Customize>WooCommerce>Checkout, and while there are some customization options (such as requiring a company name, text for accepting terms and conditions), I still cannot edit the text.

If anyone has any ideas, please let me know.