Passing a file path is just passing a string:

sub get_path {
    my $path = shift;                  # Retrieve the argument.
    print STDERR "DEBUG: Got '$path'"; # Show you got it correctly.
}

get_path('a/bcd/sample/array.list');   # Pass the argument.
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Or, did you mean something else? See How do I post a question effectively?, show us what you tried and how it failed.