====== config/schema/monmodule.schema.yml ======

<code>
/var
    /www
        /drupal
            /modules
                /custom
                    /monmodule
                        /config
                            /schema
                                monmodule.schema.yml
</code>

<code yaml>
monmodule.settings:
  type: config_object
  label: "Paramètres pour MonModule"
  mapping:
    monmodule:
      type: mapping
      mapping:
        parametre1:
          type: text
          label: "Paramètre 1"
        parametre2:
          type: text
          label: "Paramètre 2"

block.settings.monmodule_block:
  type: block_settings
  label: "Block MonModule"
  mapping:
    monmodule_block_settings:
      type: text
      label: "Parametres block MonModule"
</code>