It seems you are running Windows.
There should be both a FPVFreerider.exe file and a FPVFreerider_Data folder in the same directory.
If not, try to re-download and unpack the zip file again (perhaps to another directory).
Did the download again... put the zip into a different file and unpacked with the same error. I have the two files you name.
Check the sizes - the zip file should be about 117MB, and the unpacked FPVFreerider_Data folder should be about 270MB.
Try to right click the FPVFreerider.exe file and select "run as administrator" and see if that helps.
