You can safely delete these files since these are just caches and not the actual fonts stored on your computer. To rebuild it, you need to clear font cache on Windows or Mac.
If you are having trouble displaying or using fonts such as fonts appearing garbled, fonts refusing to switch when you want them to or giving errors or crashing the program while switching fonts, then it may indicate that your font cache is corrupted.
A cache is a file made by the operating system to make certain aspects quickly accessible and reduce fetch times and also the burden on your storage device.
