Add shortcode NFT "View on Opensea"
Sell your NFTs on OpenSea
Select one of your collections, in the list of your NFTs, click on a NFT data then click on "Get Shortcode"



You can now paste this shortcode into any of your Wordpress posts / pages

Here is the result:

You can customize the shortcode by updating this parameter "image=100" inside the shortocode in the post edit page:

Here is the result

Image parameter is equivalent to width attribute used in <img> balise.
You can buy it on OpenSea if you want ...