How can a theme define which settings for blocks are available in the block editor?

You’ll have to define the settings on theme.json. Here are the documentation links that would be of help.

https://developer.wordpress.org/block-editor/how-to-guides/themes/theme-json/
https://developer.wordpress.org/themes/advanced-topics/theme-json/

Related Posts:

  1. Proper, exhaustive documentation for wp.editor etc
  2. Edit srcset and sizes attributes in Gutenberg image, cover and gallery – blocks
  3. Add colors to existing color palette without replacing it
  4. Can you filter posts by meta key with the getEntitityRecords selector?
  5. WP Gutenberg custom block – generate theme colors from SASS and use them in the inspector and php callback
  6. create blocks programmtically on theme activation
  7. Can I customize any WordPress parent block-based theme template files by child theme like a parent classic theme?
  8. How to support Lazy Loading Assets in a WordPress Theme?
  9. WordPress Gutenberg Theme: Structure, Hierarchy and Custom Templates
  10. Gutenberg Reusable Block as part of WordPress Theme page
  11. Custom button block doesn’t work
  12. How to float an image in Gutenberg
  13. Gutenberg – editor-font-sizes in functions not working
  14. Can’t select my block by clicking on it
  15. Which file handles the block latest posts, I want to examine excerpt handling
  16. create-guten-block in wordpress theme?
  17. What VSCode extensions are there for working with block themes? [closed]
  18. What is the “correct” way to add hooks or similar PHP behavior to a blocktheme?
  19. Not able to select width of blocks inside of cover block
  20. How to check if a WordPress core block is active in sidebar
  21. gutenberg add classes to list items
  22. How do you replace content generated by custom fields with custom blocks in Block Editor?
  23. Custom Blocks as part of a theme
  24. How to wrap all titles generated by Gutenberg “Heading” block with tag
  25. How to add InnerBlock multiple times in the same block
  26. Moving post title down the page / Removing a block from a post
  27. HTML block gutenberg templates
  28. Gutenberg theme development: how to add “headers” option under styles > colors > elements?
  29. Change default rel attributes for Image Block & Button Block
  30. How to update mark-up of a gallery block in a custom theme?
  31. Auto focus RichText field
  32. How to create nested array attribute
  33. Show popover with url and option to open in new window
  34. How to Modify WP_Includes/blocks/latest_posts.php
  35. How to render block editor in wp-admin custom pages programmatically
  36. Social-Link block not loading html on page with custom theme
  37. How to diagnose wp-env environment problem
  38. Attribute form NumberControl doesn’t update when I update page before it lose its focus
  39. WP Gutenberg custom block – generate theme colors from SASS and use them in the inspector and php callback
  40. Posts Page shows Classic Editor interface not Gutenberg
  41. How can I include custom Gutenberg Blocks in a theme?
  42. Block validation failed for `core/pullquote` after adding theme support for editor-color-palette
  43. Is there a way to add classes to a page when using a Gutenberg reusable block as page layout?
  44. Correct way to make a custom block theme responsive
  45. Multiple content areas with Gutenberg – Transparent areas mid content
  46. Insert gutenberg blocks into template
  47. Template for posts of category in block theme?
  48. Can’t select my block by clicking on it on apiVersion – but using blockProps
  49. How can I use pre declared blocks in a php file?
  50. Is there any filter or action hook to remove layout classes from appearing in my templates?
  51. Full site editing templates folder vs block-templates
  52. How to set the margin on an innerBlock in a block variation?
  53. Align images to the left of the content
  54. Image and font support missing in editor when deploying theme remotely
  55. Why is my Toggle field not showing in Gutenberg?
  56. When trying to run build script with gutenberg (with SVG import) – Error: Plugin name should be specified
  57. Block to show posts from same category
  58. Unwanted spacing for cover block
  59. Activate Gutenberg group block for theme
  60. How to add posts to custom menus?
  61. How to remove search bar from a wordpress theme? [closed]
  62. How to: Update live sites theme from version control repo via plugin or library? [closed]
  63. How to customize wordpress login/register pages?
  64. Page attribute template dropdown not displayed even the syntax is correct
  65. How to add a text widget during theme activation
  66. WordPress Theme customisation CSS
  67. De-registering parent style sheet css recommended?
  68. inserting custom li class to wp_list_pages
  69. Theme check: Missing a text-domain
  70. How to determine if post has widget content?
  71. WP Customize refresh problem
  72. Set multiple templates per post
  73. My javascript jquery won’t work?
  74. Displaying recent post excerpts on static front page
  75. approach to pass additional parameter in post URL
  76. WordPress Media Uploader in page template (On Front-end)
  77. Replace function in a child theme
  78. How to register and enqueue JavaScript files without breaking plugin dependencies?
  79. Extract all shortcode data from post into loop variables?
  80. Adding the_content() return warning count()
  81. Copying the theme style files and images to duplicate the website but with a difference
  82. How to enqueue a script which is type module without using script_loader_tag filter?
  83. How do I include a partial from a directory below a wordpress theme directory?
  84. Ajax call returns 0 when add_action is inside a class in functions.php
  85. Is it possible to have a Theme with built-in physical page files?
  86. header, stylesheet not being read
  87. first excerpt fine, subsequent post excerpts shift to the right instead of displaying vertically [closed]
  88. List categories of a post hierarchically?
  89. Custom Post Types set up, how do I style the main slug page?
  90. What are the permalinks options for “Category” base and removing it?
  91. How to register dynamic settings in WordPress Customizer?
  92. How to add audio files to audio player in WordPress custom theme?
  93. Data Validation & Sanitization for Big HTML Blocks
  94. Using ‘get_template_directory_uri’ correctly
  95. Adding a space between next and previous post links
  96. Next post in category
  97. Setting different CSS for all pages except home.php
  98. load src of images that attachs in wordpress’s post
  99. Add Field To All Pages
  100. Creating custom function in wordpress to return data from database