You can download the latest version of Ubuntu Linux from the Ubuntu website (https://ubuntu.com/download/desktop).
To download the ISO file for Ubuntu Linux, click the "Download" button under the "Ubuntu Desktop" section. This will download the ISO file for the latest version of Ubuntu Linux.
Alternatively, you can download the DVD file for Ubuntu Linux by clicking the "More options" button and selecting the "64-bit DVD" option under the "Download Ubuntu Desktop" section. This will download the DVD file for the latest version of Ubuntu Linux.
Keep in mind that the ISO file is a smaller, more portable version of Ubuntu Linux that can be used to create a bootable USB drive or DVD. The DVD file is a larger version of Ubuntu Linux that includes more software and can be used to install Ubuntu Linux on a larger number of systems.
For more information on downloading and using Ubuntu Linux, you can refer to the Ubuntu documentation.