I tried using push($myarray[0], $_) within the for loops, but that didn't work.

You almost got it right... should be push @{$myarray[0]}, $_;

I see NetWallah has posted a good solution, here are my alternatives...

use strict;
use warnings;
use Data::Dumper;

my @array = ();

for my $i (0..1) {
    for ($i*5+1..$i*5+5) {
        push @{$array[$i]}, $_;  # push an element at a time
    }
}

print Dumper(\@array);

@array = ();

# one-liner with map and slice.
@array[0..1] = map { [ $_*5+1 .. $_*5+5 ] } 0..1;

print Dumper(\@array);
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