That likely isn’t how to properly edit your php.ini.
Are you using a dedicated server or VPS? If not does your host even allow you to modify your php.ini settings? If you’re on shared hosting you probably can’t, though some will actually provide you a way. You might be able to use the .htaccess file, assuming they use Apache for the web server and allow you to do it that way. Note that you may have to refresh or restart Apache for the changes to take effect.
Either way, since you aren’t really sure, you should contact your host and ask them to set the error reporting to a proper production setting so you don’t get strict standards errors. If they don’t understand that and can’t do that for you then I would highly recommend getting a different host that knows what they’re doing.