If you're having trouble getting a file from your code virtual machine onto your actual computer to submit it onto Gradescope, never fear, an easy solution is here:
Right click on the desired file from the file explorer (normally on the left panel) on your code viewer.
Select 'Download' and the file will download to your browser's default download location (typically your 'Downloads' folder).
Voila! You have successfully moved a file from your online code to your machine.