RAC-225: add usage on checkbox page from notion

akeneo-design-system/Introduction.stories.mdx

@@ -109,7 +109,7 @@ import { linkTo } from '@storybook/addon-links';
 
 # Welcome to Storybook
 
-Storybook helps you build UI components in isolation from your app's business logic, data, and context.s
+Storybook helps you build UI components in isolation from your app's business logic, data, and context.
 That makes it easy to develop hard-to-reach states. Save these UI states as **stories** to revisit during development, testing, or QA.
 
 Browse example stories now by navigating to them in the sidebar.

akeneo-design-system/src/components/Checkbox/Checkbox.stories.mdx

@@ -19,6 +19,23 @@ import { Checkbox } from "./Checkbox.tsx";
 
 # Checkbox
 
+## Usage
+The checkboxes are applied when users can select all, several, or none of the options from a given list.
+
+### Checkbox states
+The checkbox control allows three states: selected, unselected, and undetermined. The undetermined state comes into play when the checkbox contains a sublist of selections, some of which are selected, and others aren't.
+
+Users must be able to check the box by clicking directly on the box or by clicking on its label.
+
+### Content
+#### Title
+
+If necessary, a header can accompany a set of checkboxes to provide more context or clarity.
+
+#### Labels
+
+Always use clear and concise labels for the checkboxes. The labels appears on the right of the checkboxes.
+
 ## Playground
 
 Use this playground to test the checkbox component