Hi there @madedaintytings. I can definitely look into this with you. Which theme are you currently using? Has the "Add to cart" button always been missing or is this a recent change?
Usually your product pages will have an add to cart button automatically included, but if it's not there you should be able to add this button from within your theme editor. To get into your theme editor you'll want to go to Online store > Themes and click Customize next to the theme you are working with. Once there, you will want to make sure you are viewing your Default product page template. Then you will want to click Add block under the Product information section and you should see the option to add the Buy buttons block. This will cause the "Add to cart" and dynamic checkout button to appear. I've included a screenshot showing these steps below. You can also read more about using sections and blocks in your theme editor on this page.
Please let me know if you have any questions about this. I'm happy to help further!
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