source $1
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This is including a file, which is specified at the command line as your first argument. It is most likely a config file of some sort.

echo "--0--"
echo $lnPARAM[0]
echo $lnVAL[0]
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This is printing the contents to two "arrays" to the screen, presumably they are defined in the file being sourced.

So all you are doing is:

1. specify a config file for reading
2. read the contents, put them into arrays for later usage
3. loop over array contents and print them out

You generally don't "include" config files in Perl programs. Instead, you parse them out using a loop like:

while (<STDIN>) {
  my $line = $_;
  # do something with $line
}
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This handles contents piped in using a command like:
#cat config.txt | perl myscript.pl

More likely, though, you'll want to read a specified file using the open function.

This is probably the most simple "real" script you could write, so it is not that hard to convert this at all.