The Custom Block Blocks can be added via the Paragraph Builder on the Front Page, Basic Page, and Landing Page content types. Blocks are boxes of content that can contain text
Instructions
Embed a Block
...
In the Admin Toolbar, navigate to Structure > Block layout > Add custom block
Click the Basic block link
Enter a Block description
Enter the Body of the block
Click the Save button
Edit a Custom Block
In the Admin Toolbar, navigate to Structure > Block layout > Custom block library
Click the Edit button in the Operations column
Make any desired changes
Click the Save button