Why are my images blurry in WordPress

WordPress.org

Since you asked your question under "General questions", I will not go into the subject of "product images" in my answer (which are not available in WordPress without an additional plugin such as WooCommerce).

In general: Images become blurred if they are displayed larger than they are in the original. If I open the developer tools in the browser and hover over one of the integrated images, it shows me that the image is displayed significantly larger than it actually is. Since the resolution does not allow that, the browser has to "extrapolate" the image, which leads to a blurred display:

(I'm assuming that you would be fine with a reproduction of an image of your website in the context of a quote.)

Under Settings> Media you can specify image sizes for future uploaded photos. Check the documentation for your purchased theme (which we cannot support here because we cannot access it for free) to see whether your theme recommends certain image sizes.

Images that you have already uploaded will not be adjusted afterwards due to the newly specified image sizes. But there is a plugin for this: Regenerate Thumbnails.

For quality reasons, WordPress will only save smaller scaled images of uploaded images, but not extrapolate images, because this also leads to the aforementioned loss of quality. In this case, however, the theme seems to display the small image larger.