You’re able to enable PHP for certain domains by adding a conf file, named after your domain name followed by .conf (e.g. example.com.conf) to /home/user-data/www .
$ cat /home/user-data/www/example.com.conf
location ~* \.php$ {
include fastcgi_params;
fastcgi_pass php-fpm;
fastcgi_index index.php;
}