I want to create a button whit this action : "create a backup from my project in a special path" .
How can I do it ?

Since most Access apps should be split between back end (tables) and front end (everything else), a split app makes this easy.

You can use the FileCopy method to make a copy of the back end in a specified location. Since you should have backup copies of your front end in a development area, its really only necessary to backup the back end(s).