It appears that MySQL is not installed or not included in your path; if it is installed, locate the
mysqlexecutable and add the directory in which it is located into your PATH environment variable.
For Apache and PHP, make sure that they are set to serve the correct directories (such as
/Library/Webserver). They appear to be denied access because they are attempting to serve the root directory
/. If the directory is correct, check the permissions and ownership of the directory.