In addition to other suggestions above, if your configuration is going to always be the same for a given script, you could consider making it a singleton object. Then the constructor for TestClass could create a private configuration object without it having to be explicitly passed in.

package ConfigFile;

my $self;

sub new {
    if ( ! defined $self ) {
       my $that=shift;
       my $class=ref($that) || $that;
       $self = { Verbose => 1, RaiseErrors => 0};
       bless $self, $class;
    }    
    return $self;
}

sub get_conf {
   my $self=shift;
   my $param=shift;
   
   my $result; # get result
   
   return $result;
}

1;
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package TestClass;

require ConfigFile;

sub new {
    my $that=shift;
    my $class=ref($that) || $that;
    my $self={ 
        Verbose => 1, 
        RaiseErrors => 0, 
        Config => ConfigFile->new()
    };
    bless $self, $class;    
    return $self;
}

sub anything {
  my $self=shift;
 
  # Access config via $self->{Config}->get_conf()

  return;
}

1;
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