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and Thanks for your Good question.
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So I will check and provide a solution here.
Hey there, @DonnaDavies!
Ryder here, from the Social Care Team at Shopify. Thanks for posting! I'd be happy to see if we can find a way for you to remove the add to cart pop-up from within your theme. I attempted to add a product to the cart in my own test store's Venture theme, and it appeared differently than how yours seems to appear:
Since you're using a Shopify free theme, you may be eligible for 60 minutes of theme support. For this purpose, I've preemptively sent you an email to your Community Forums email address. If you'd like our Theme Support Specialists to take a look at your theme and see whether this is something they'd be able to assist you with, please respond to this email with your shop's .myshopify.com URL from your shop account's email address on file. I can then look at authenticating you on the account before escalating it their way.
If you're comfortable making coding customizations on your own, I recommend creating a duplicate of your theme before proceeding with any changes. That way, you can always revert back to your old copy if you make any mistakes. You can then try following the second half of the customizations in this Community Forums post response by Vix. This post is from 2016, and I'm unclear whether it would still apply to the standard Venture theme; however, because your add to cart pop-up appears differently in your theme than it does in mine, your code may also appear differently. Have you added any apps or made any coding customizations to your theme relating to the cart at all?
Finally, if neither of the above solutions works for your business, you can also consider hiring an Expert to assist you with theme customizations.
I hope this helps! Please let me know if there's anything I can clarify.