hi @ykh525050 ,
to add a featured image to a post you have to use the HTTP Request node and the Wordpress APIs that are documented here:
If you want to add a featured image you will have to:
- Create the post
- Add the image to Wordpress: using this Wordpress API Media – REST API Handbook | Developer.WordPress.org
- Set the image as featured image in the post: using this API Media – REST API Handbook | Developer.WordPress.org
You can see a full example here:
Let us know if this helps or you need more support
Best