Is it possible to change file status (from read only to read and write) for multiple files/folders at once?

Question

I moved all my web files/folders from my default MAMP directory to a more manageable location. Now all the files and folders have been changed to read only.

I figured out how to change the status per one by one, but that would take a lot of time. Is there a way to change all the files and folders to "read and write" all at once