On your Moodle site, you can show content from anywhere on the web using a link. You add the link to your course's home page. When the student clicks on the link, the linked item is displayed.
When using the content from outside sites, you need to consider the legality and reliability of using the link. Is it legal to display the material within a window on your Moodle site? Will the material still be there when your course is running?