There are no dumb questions ... just a learning curve.
Normally, files should not be moved until the project is complete. If they have been, VP will prompt to find (resolve) them. Be sure to re-save the project.
Save Project File AS routinely, giving it a unique # or name, so as not to overwrite prior saves. Using Save Project Files (no AS) will overwrite. From the HOME tab, that choice is available by clicking the chevron to the right of the Save Project button on the toolbar. That's your protection.
If you want portable copies of all source files, as well as the VPJ control file that tells the program what to do, first have the completed project on the timeline.
Then click the 3-lined Menu item (top-left) | FILE | SAVE PORTABLE PROJECT AS. 
That creates a numbered folder (likely in the PC's DOWNLOAD folder). But you can move or copy it anywhere, perhaps to an external drive. Open it and double-click the VPJ file to load the project - on any PC that has Videopad installed. Original source files are unaffected.
When reloading a project, files will be restored quickly if the cache hasn't been cleared (OPTIONS | DISK tab). They're already in memory.