Due to security reasons, the checkout page on Shopify is inaccessible and only some very basic information can be altered (such as changing the text that is already visible on the page).
Any changes on the checkout page are only possible if you are on the Shopify Plus account, for which the price starts at $2000 a month. You can check more details about the Shopify Plus plan here:
However, if you are not on the Shopify Plus plan, we might be able to assist you by making the changes on the cart page of your store. To find out more about what we can do for you, feel free to reach out to us via chat or via email to [email protected].
If you are on the Shopify Plus plan, reach out to us anytime and we can also check what can be done to assist you.