To provide the best advice possible, can you specify what the statement of this hypothetical agreement/disagreement is? If you need to add an 'Agree To Terms And Conditions' Checkbox, there are a couple of options you can consider for adding a terms and conditions checkbox to your theme.
Assuming your store has enough complimentary design time left and you are using Shopify free theme, our team may be able to customize this for you.
You can reach out to our Contact Us page at this link. Then log in to your store. It will allow us to verify you as the store owner securely. Once you have successfully logged in, you should be able to reach out to a Support Advisor and discuss the customization request.
Otherwise, I'd recommend taking a look at our directory of certified developers on Shopify Experts.
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