Plugin: facebook widget for closed or public group

Hi, I found a lot of very good facebook widget to put on my website, but all of them contain “facebook page”, “facebook community”. what I need?
I need to put a widget of my facebook closed group (i could make it to public group if it is necessary) to my website. And what i need more exactly is just that people could see (on my website) nice cover picture and call to action ( join to group). I do not need posts, comments, and so on.
Is there a plugin or a way to do this?
I need similar effect like https://www.ads-software.com/plugins/easy-facebook-likebox/. And I have tried couple more plugins like this, but all of them was worthless about facebook close or public group.
Thanks