To add videos on Drupal 8, follow these steps:
1. Log in to your Drupal 8 website
2. Go to the “Content” section in the main menu
3. Click “Add Content“
4. Select “Video” from the content types list
5. Fill in the necessary details for your video, such as the title and description
6. Click “Upload” to select your video file
7. Select and upload your video file from your computer or other source
8. Choose a thumbnail image for your video, if desired
9. Click “Save” to publish your video
You can also use a module like Video Embed Field, which allows you to embed and display videos from various sources like YouTube, Vimeo, and many others. With this module, all you need to do is add the video link in your content, and the module will automatically embed it for you.