Installing WAMP Server

On this tutorial at the 4.1 configuration i cannot find any of the files i have to edit
Set level of error reporting – remove the ; at beginning of line to enable:
error_reporting = E_ALL ^ E_DEPRECATED (~line 112)
Log PHP errors – remove the ; at beginning of line to enable:
error_log = “c:/wamp/logs/php_error.log” (~line 639)
Increase maximum size of POST data that PHP will accept – change the value:
post_max_size = 50M (~line 734)
Increase maximum allowed size for uploaded files – change the value:
upload_max_filesize = 50M (~line 886)

how can i fix this issue ? my wamp version is 2.5