Make your configuration a global variable instead of a lexical variable and you can access it from anywhere:

package ConfigFileRead;
...
use vars qw(%User_Preferences);
...
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# main program
...
require ConfigFileRead;
use Data::Dumper;
print Dumper \%ConfigFileRead::User_Preferences;
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Or, alternatively, make your subroutine readConfigFile return a reference to the configuration:

# in ConfigRead.pm
sub readConfigFile {
    ...
    return \%User_Preferences;
};

# main program
my $config = ConfigFileRead::readConfigFile();
print Dumper $config;
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