How to use the undownload script.

Im bad in english and still begginer.
how to use a script like this copying it?

Spoiler for:

#==============================================================================
# ** Custom Commands
#------------------------------------------------------------------------------
#  © Dargor, 2008-2009
#  03/03/09
#  Version 1.15
#------------------------------------------------------------------------------
#  VERSION HISTORY:
#   - 1.0   (09/03/08), Initial release
#   - 1.1   (15/03/08), Added support for Party Commands
#   - 1.2   (15/03/08), Added support for Actor Commands
#   - 1.2.1 (15/03/08), Bug fixed with Selectable Window's contents
#   - 1.3   (24/03/08), Added the 'Selection' method to Window_Selectable
#   - 1.4   (08/05/08), Works with the 'Selection' method
#   - 1.5   (08/06/08), Added support for command substitution based
#                         on an actor's class ID
#   - 1.6   (13/06/08), Added support for Title Screen Commands
#   - 1.7   (13/06/08), Bug fixed when disabling default commands
#   - 1.7.1 (16/06/08), Increased compatibility
#   - 1.8   (18/06/08), Menu Index has been corrected when comming back of
#                       default scenes (Item/Skill/Equip/Status/Save/End).
#   - 1.9   (18/06/08), Added support for enabling/disabling commands.
#   - 1.9.1 (05/09/08), Minor revisions
#   - 1.10  (07/09/08), Added support for command icons
#   - 1.11  (16/02/09), Added support for message codes in command names
#   - 1.12  (16/02/09), Added a "Rainbow" command feature
#   - 1.13  (16/02/09), Added support for message codes in item names
#   - 1.14  (23/02/09), Fixed a bug when drawing command names
#   - 1.15  (03/03/09), Fixed a bug with font characters width
#------------------------------------------------------------------------------
#  INSTRUCTIONS:
#     1) Place this script above all custom scripts and below all
#         default scripts
#     2) To change the default menu commands, use:
#           - $game_system.menu_commands = [string1, string2...]
#               or
#           - $game_system.add_menu_command(index, command)
#               or
#           - $game_system.remove_menu_command(command)
#     3) To change the default party commands, use:
#           - $game_system.party_commands = [string1, string2...]
#               or
#           - $game_system.add_party_command(index, command)
#               or
#           - $game_system.remove_party_command(command)
#     4) To change an actor's battle commands, use:
#           - $game_actors[id].commands = [string1, string2...]
#               or
#           - $game_actors[id].add_command(index, command)
#               or
#           - $game_actors[id].remove_command(command)
#------------------------------------------------------------------------------
#  NOTES:
#     - When using the following methods:
#             > $game_system.add_menu_command(index, command)
#             > $game_system.remove_menu_command(command)
#             > $game_system.add_party_command(index, command)
#             > $game_system.remove_party_command(command)
#             > $game_actors[id].add_command(index, command)
#             > $game_actors[id].remove_command(command)
#       'command' can be a String or an Array
#     - This script overides the following methods:
#             > Window_PartyCommand
#               <> initialize
#             > Window_ActorCommand
#               <> initialize
#               <> setup
#             > Scene_Menu
#               <> create_command_window
#               <> update_command_selection
#               <> update_actor_selection
#             > Scene_Battle
#               <> update_party_command_selection
#               <> update_actor_command_selection
#         This script will be incompatible with any other scripts
#         modifying these methodsunless they are based on the
#         Custom Commands script methods.
#     - Some message codes are available for command and item names:
#             > Color Change: \C[x]
#             > Variable:     \V[x]
#             > Actor Name:   \N[x]
#==============================================================================

Tell me PLEASE!!!!!?

What is your first language? there are a lot of non-English language forums out there if you have trouble with English.

In any case, to put a script in your game, you need to go into your project. Go to the script editor by clicking the pencil and paper icon on the top bar (or just press F11). You should see a long list of the default scripts. Scroll down until you get to Main. Right-click above it and choose Insert New option. Name the new slot after the script or by whatever naming mechanism you like. Then go into the large white box on the right and paste the script into it.

Wait a minute, that script is a giant comment box. It really isn't going to do anything.