All webservers have the "php.ini" file (both Windows and Linux Servers). Normally, if you have shared hosting, your web host may not let you edit the file. In that case you will have to contact your webhost and ask them to make the needed changes for you.
If you have a server locally and have access to the root directories of it, you can simply use a text editior to modify this file, and then restart apache (or whatever other web server you run) so that they changes made take effect.
