First, don't post code you didn't run. You're missing the word "sub" in a couple of places.

Secondly, since the error is in Module2, it would help if you could show it.

I suspect you did

use Module qw(:all);
package Module2;
...
cook();
...
[download]

when you should have done

package Module2;
use Module qw(:all);
...
cook();
...
[download]

The former imports everything into the wrong package.