Editing website preview photo and title

How do I change the website preview photo and title?! Please help! If you copy and paste it into an imessage or a Facebook comment it looks completely different! try it out to see what I mean.

Here is my site Read-Only: **[LINK][1]**Webflow - Saddles De France

Im not sure if you are talking about opengraph

try this:
• Go into pages

• then into page settings

• scroll until opengraph and change the image and tittle