The Like button is the quickest way for people to share content with their friends.
A single click on the Like button will 'like' pieces of content on the web and share them on Facebook. You can also display a Share button next to the Like button to let people add a personal message and customize who they share with.
To add Facebook like button:
1. Open developers.facebook.com/docs/plugins/like-button/
2. In the "" field enter page URL you want to like.
3. Choose Layout and Action Type.
4. Click Get code.
5. Open "Iframe" tab and copy the code.
6. Open your website "Text" block editor .
7. Click on "html" and you'll see a box expand. Paste the code for your plugin and click "Update".
8. Click Save.