If you receive a USB drive with tomography data (for example from a dentist), the files often come in DICOM format (extension .dcm).
These files can be read using 3D Slicer, a free and open source software platform for medical image informatics, image processing, and three-dimensional visualization. It is available for Windows, Linux, and Mac.
You can download it from: https://download.slicer.org/
On the USB drive, you will likely find a Data folder containing a list of .dcm files. You can simply point the 3D Slicer UI to that folder to load and visualize the data.
I tested this on Linux (Debian) in a Chromebook and it works fine.