[Backport 12.4] Add prerequisites at the beginning (#606)

* [TASK] Add prerequisites

* [FIX] Add prerequisites to toctree

* [FIX] Adjust Prerequisites

---------

Co-authored-by: Kiebele <[email protected]>

Author: github-actions[bot]

Documentation/Index.rst

@@ -21,6 +21,14 @@ system and detailed information on how to install TYPO3.
     :class: pb-4
     :card-height: 100
 
+    ..  card:: Prerequisites
+
+        In this section we mention the prerequisites that you need before
+        you start with this tutorial.
+
+        ..  card-footer:: :ref:`See the prerequisites <Prerequisites>`
+            :button-style: btn btn-secondary stretched-link
+
     ..  card:: Concepts
 
         Written for new users, this chapter introduces some of TYPO3's core
@@ -29,9 +37,6 @@ system and detailed information on how to install TYPO3.
         ..  card-footer:: :ref:`Learn about the basic concepts <Concepts>`
             :button-style: btn btn-secondary stretched-link
 
-        ..  card-footer:: :ref:`Learn more about TYPO3 Concepts <Concepts>`
-            :button-style: btn btn-secondary stretched-link
-
     ..  card:: Installation
 
         The installation chapter provides detailed instructions on how to
@@ -78,6 +83,7 @@ system and detailed information on how to install TYPO3.
     :hidden:
     :titlesonly:
 
+    Prerequisites/Index
     Concepts/Index
     Installation/Index
     FirstProject/Index

Documentation/Prerequisites/Index.rst

@@ -0,0 +1,77 @@
+:navigation-title: Prerequisites
+..  include:: /Includes.rst.txt
+
+..  _prerequisites:
+
+=================================
+Prerequisites to start with TYPO3
+=================================
+
+Before you start working on this tutorial, you should have DDEV installed on
+your computer.
+
+This TYPO3 tutorial assumes that the reader has some basic knowledge in the following areas:
+
+*   `HTML, CSS and JavaScript <https://www.w3schools.com/html/default.asp>`__
+*   `Basic Command Line Interface (CLI) Commands <https://www.w3schools.com/whatis/whatis_cli.asp>`__
+
+..  _composer_cheat_sheat:
+
+Composer cheat sheet
+====================
+
+Composer is a powerful tool for managing dependencies in PHP projects, including
+TYPO3. Here you will find an overview of the four most important commands with a
+simple explanation of what they do.
+
+..  _composer_require:
+
+composer require
+----------------
+
+..  code-block:: bash
+
+    composer require vendor/extension-name
+
+It installs a new package (e.g. a TYPO3 extension) and automatically adds it to your :guilabel:`composer.json`.
+Composer determines the appropriate version based on your current configuration.
+All required dependencies for the package are also installed.
+
+..  _composer_remove:
+
+composer remove
+---------------
+
+..  code-block:: bash
+
+    composer remove vendor/extension-name
+
+Uninstalls an existing package from your project.
+Removes the entry from :guilabel:`composer.json` and deletes related files from the
+:guilabel:`vendor` folder.
+Removes unused dependencies that were only required fro the removed package.
+
+..  _composer_install:
+
+composer install
+----------------
+
+..  code-block:: bash
+
+    composer install
+
+It installs exactly the versions specified in the :guilabel:`composer.lock` file.
+
+..  _composer_update:
+
+composer update
+---------------
+
+..  code-block:: bash
+
+    composer update
+
+It updates all installed packages to their latest version, as allowed by the version constraints in :guilabel:`composer.json`.
+The :guilabel:`composer.lock` file, which records the exact package versions, is updated.
+Downloads the updated packages to the :guilabel:`vendor` folder.
+