MacBook with only white screen and a folder.
White screen with folder
[Re-Titled by Moderator]
Earlier Mac models
Question marked as
It means no bootable OS volume was found. It could mean a file system issue, severely damaged OS, or a failing drive.....the latter is most likely on a system that old.
Try running the Apple Diagnostics to see if any hardware issues are detected.....it won't detect most failures.
Here is an Apple article explaining what to do with a blinking folder with a question mark in it:
If your Mac starts up to a question mark - Apple Support
Just for reference, here is another Apple article for various startup screens you may encounter:
If your Mac doesn't start up all the way - Apple Support