Inline versus site-wide blocks
Drupal provides the ability to use two types of block content – inline and site-wide (reusable) blocks. Using Layout Builder, users can drag and drop site-wide blocks into a page layout or create and place inline blocks that are unique to a given page.
After creating a new Flex Page, click Layout > Add block > Create content block.
Sections are the top-level building blocks of page layouts. Blocks exist within a section.
When Layout Builder appears, click “Create content block” at the top of the Layout Builder tray. The list of available inline block types which include the Drupal Kit’s Custom content components will appear (see image below). Chose the block you want and complete the form and save. The new inline block content will now appear on the page. Blocks created this way are only available in this particular layout and will not be available in the Blocks UI.
Use Drupal’s site-wide block system at Content > Blocks (/admin/content/block) to create new blocks for use on multiple pages.
After creation, these blocks will be available on Flex Pages under Layout > Add block > Content block:
Users with the ability to modify the site-wide layout can also place these blocks from the Block Layout interface at Structure > Block layout (/admin/structure/block):