The Custom Block can be added via the Paragraph Builder on the Front Page, Basic Page, and Landing Page content types.
Instructions
Embed a Block
In the Paragraph Builder list of types, click the Add Custom Block button
Select the desired block in the Block field
Click the Save button
Create a Custom 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