Composer cannot find drupal/commerce in a specific module
You need to add the Drupal repository to composer.json in your project.

"repositories": [
  {
    "type": "composer",
    "url": "https://packages.drupal.org/8"
  }
]


Note that after you do this and run composer require/update, it will create a vendor directory in your module folder. You'll want to delete this folder, as you only want your dependencies to be added when the module is added to your project, and your project's composer.json should install the dependencies in the correct directory.