my ($field, $value);

# then, inside your loop...
... { ...

  my @lines = (
    [ "NAME", "$fname $lname" ],
    [ "AGE", $age ],
    [ "WHATEVER", $whenever ],
    # ...
  );

  for (@lines) {
    ($field, $value) = @$_;
    write FORMAT;
  }

... } ...

format FORMAT =
@<<<<<<<<<<<<<   @<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
$field,          $value
.