How to set featured image in order to be shared in facebook
The Yoast SEO Plugin also comes with the ability to add a custom Facebook thumbnail to each individual post or page.
Simply install the Yoast SEO Plugin. After you’ve installed and activated, it’s time to set up a Facebook thumbnail into whatever post you want.
Here I will mention the way to get the token for Facebook Page
First of all try to check if you have crruent token and see when it will be expired by this link
Now the first step is to get the user token
some times when you want to share a link on facebook and your website is protected by Cloudflare you will have this error
"access denied used cloudflare to restrict access"
to solve it you have to "Whitelist Facebook ASN IP in Cloudflare"
So now how you will Whitelist Facebook ASN IP in Cloudflare, to do it follow the below steps
you can whitelist Facebook’s entire IP range in Cloudflare’s Firewall settings.