user:pass user1:pass1 use:pas
         ^           ^

##</code><code>##

user:pass
user1:pass1
use:pas

##</code><code>##

#!/usr/bin/perl
use 5.016;
use warnings;
# NOT JUST BTW: this will not work without modification for some possible forms of data!

my $list = "user:passer use:pass user1:pass1";

say $list;
say "That was \$list; these are the elements of \@arr:";

my @arr= split / /, $list;

for (@arr) {
    say $_;
    my $current_element = $_;
    my ($first, $second) = split /:/, $current_element;
    say "\$first: $first & \$second: $second";
}

##</code><code>##

user:passer use:pass user1:pass1
That was $list; these are the elements of @arr:
user:passer
$first: user & $second: passer
use:pass
$first: use & $second: pass
user1:pass1
$first: user1 & $second: pass1