You may think that Apple’s DVD Player app disappeared with macOS Mojave in 2018. It hasn’t and can be found in macOS Tahoe, though Apple has done its best to hide it.
The easiest way is to use Spotlight. Click the little Spotlight icon in the upper right corner of your Mac’s screen. Search for “DVD Player, and the app’s icon will appear at the top of the Top Hits. Double click on the icon, and the app will launch.
Once launched you can open a DVD by going to File > Open DVD Player. Of course, since Apple no longer makes a Mac with a built-in DVD player/slot, you’ll need a product such as the Apple USB Superdrive.
The problem is that Apple has discontinued the product, so it’s hard to find a new one. You’ll probably have to search the Internet for a used one. Of course, there are various third party products you can use.

Once you get your hands on one, Attach the SuperDrive. It must be attached to a USB-A port, so you may need an adapter to connect it, depending on your Mac model. It’s compatible with Macs introduced in 2008 or later that don’t have a built-in optical drive.
Now launch DVD Player, and select Open DVD Media.
To eject a disc, click Finder in the Dock, then choose File > Eject. Or, if your keyboard has an eject key, press and hold the eject key .



