I was trying to figure out how to print it to the output file and was hoping that would of made it easy but I was wrong. I modified it to this now:

use warnings;
use strict;

my $infile="clients.txt";
open my $in,  "<", $infile     or die $!;
open FH, ">" , "clients.csv" or die $!;


print FH join ("," => qw(Name Phone E-mail)),$/;
while (<$in>) {
    chomp;
    print FH $_, "\t";
    print FH $/ if $. % 3 == 0; # note here 
}
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This gets the information into the csv file however I still need to modify the formatting, probably with a printf? What currently happens with this script is it creates the three columns "Name, Phone, Email" but the Name field is just the first name of the people while the Phone field gets EVERYTHING else. Would a simple printf or something solve this issue?

I recommend you clearly separate the parsing of the input from the formatting and outputting of the CSV records. This is a more maintainable and less error-prone technique than inputting/parsing and formatting/outputting simultaneously. I also think using modular arithmetic with $. ($INPUT_LINE_NUMBER) is less clear than simply reading each trio of lines explicitly as AppleFritter demonstrated here.

I also recommend you use autodie, explicitly specify the character encodings of the two text files, and explicitly close both file handles.

use autodie qw( open close );

my $input_file  = 'clients.txt';
my $output_file = 'clients.csv';

open my $input_fh,  '<encoding(UTF-8)', $input_file;
open my $output_fh, '>encoding(UTF-8)', $output_file;

# Process the client data file...

close $input_fh;
close $output_fh;

exit 0;
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