Article in English: On your computer's CD tray, you should see the "DVD" logo engraved or painted on. This is necessary if you want to be able to rip the DVD.  If you don't see the DVD logo on or near your computer's tray, you probably don't have a DVD drive. You'll need to buy an external DVD drive or use a different computer. Skip this step if your computer doesn't have any tray or slot for discs. If you have a computer which doesn't include a DVD drive, you'll need to buy an external USB DVD drive and attach it to your computer before you can rip a DVD in VLC. If you're using a Mac, you'll most likely need to buy a DVD drive which includes a Thunderbolt 3 (USB-C) adapter. You can also buy a USB 3.0 to USB-C adapter cable to bridge the gap between your Mac and your DVD drive. If you don't have VLC Media Player installed on your computer, go to https://www.videolan.org/vlc/index.html in your computer's web browser, click Download VLC, and do the following:   Windows — Double-click the downloaded setup file, click Yes when prompted, select a language, click OK, click Next three times, click Install, and click Finish when prompted.  Mac — Double-click the VLC DMG file, then click and drag the VLC icon onto the Applications folder, Open your computer's DVD tray, place the DVD in the tray with the logo side facing up, and close the tray. At this point, you're free to proceed with ripping your DVD on Windows or on a Mac. If any windows open when you do this, close them before proceeding.

Summary in Vietnamese:
Bạn cần chắc chắn rằng máy tính có đầu đĩa DVD. Mua ổ đĩa DVD gắn ngoài nếu cần thiết. Cài đặt VLC nếu như chưa có. Cho đĩa DVD vào máy tính.