Creating a copy of a php page

Hi guys hope u r all well.

What Im trying to achieve as the final result is the following...

====================================================== test.php

Please select what menu level you wish to create..
< select.... >                       <------------------- user selects from the following 4 files (templates)
-- menu1_x.php
-- menu2_x_x.php
-- menu3_x_x_x.php
-- menu4_x_x_x_x.php  

<Create new file>              <-------------------------- upon selecting above, they click on create new file

Enter new filename: ____________________   <-------- they enter a new filename here

<submit>        <-------------------------------------------- they click submit to have the new file created

=========================================================

# The 4 "template" files upon which a new file is created are as follows...

<docroot>/simeswiki/templates
menu1_x.php
menu2_x_x.php
menu3_x_x_x.php
menu4_x_x_x_x.php  

So,
after the user selects one of these, this selection is used as the basis upon which to copy

eg. selection is menu2_x_x.php

Now, when the user clicks on create new file..... menu2_x_x.php
is the source file in the following.....

cp menu2_x_x.php <target_new_file>.php

New files to be saved in <docroot>/simeswiki

Any help on this would be greatly appreciated.