category feature image | WordPress.org

How do I set the category page’s feature image? I don’t want the feature images for each post to change. I just want to set individual feature images for each category. That way I can send a link to a category and get the correct type of image for the category in Facebook Messenger, etc.

For example I have a page about fireworks: https://hokkaido.a4jp.com/category/en-fireworks/
Just now the site’s main image of a flower field is showing. I want to set the image as fireworks.

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